BIVALVIA, Linnaeus, 1758

Groves, Lindsey T. & Squires, Richard L., 2018, Annotated Catalog of the Fossil Invertebrates Described by, and Named for, William More Gabb (1839 - 1878), Zootaxa 4534 (1), pp. 1-150: 18-59

publication ID

https://doi.org/10.11646/zootaxa.4534.1.1

publication LSID

lsid:zoobank.org:pub:6640EBBE-839A-4365-8293-B3AB088DCCC8

DOI

http://doi.org/10.5281/zenodo.3798640

persistent identifier

http://treatment.plazi.org/id/F1260A76-FFA8-FFD8-FF43-FA50FE16F945

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Plazi

scientific name

BIVALVIA
status

 

BIVALVIA 

Subgenera and Genera

Anthonya Gabb, 1864b: 181–182  . Type Species: Anthonya cultriformis Gabb, 1864b: 182  , pl. 30, figs. 236–236a, by monotypy.

Bothrocorbula Gabb, 1872c: 274  ; 1872d: 247. Type Species: Corbula viminea Guppy, 1866: 293  , pl. 18, fig. 11, by monotypy. Remarks: Considered a subgenus of Corbula  by Anderson (1996: 12).

Clisocolus Gabb, 1869b: 188–189  . Type Species:? Loripes dubia Gabb, 1864b: 177  , pl. 24, figs. 170–171, by OD.

Conchocele Gabb, 1866: 27–28  . Type Species: Conchocele disjuncta Gabb, 1866: 28  , pl. 7, figs. 48–48b, by monotypy. Remarks: See generic revision by Oliver & Frey (2014: 465–466).

Cymbophora Gabb, 1869b: 180–181. Type Species: Cymbophora ashburnerii Gabb, 1864b: 153, pl. 22, fig. 127, by monotypy (see Saul 1974: 1070).

Cyprinella Gabb, 1864b: 170  . [Junior homonym of Cyprinella Girard, 1857  ]. Type Species: Cyprinella tenuis Gabb, 1864b: 170–171  , pl. 23, figs. 151–151a, by monotypy.

Eriphyla Gabb, 1864b: 180  . Type Species: Eriphyla umbonata Gabb, 1864b: 180  , pl. 24, figs. 162–162a, by monotypy.

Granocardium Gabb, 1869d: 266  . Type Species: Cardium (Granocardium) carolinum d’Orbigny (1844: 29–30  , pl. 245) by SD of Stewart (1930: 264). Remarks: Stewart (1930: 264) proposed that because Granocardium  has a different ornamentation than Trachycardium  , the former seems “better treated as a distinct genus.” Schneider (1998: 61) recommended that Granocardium  be considered as the subjective senior synonym of Criocardium (Conrad, 1871).

Here Gabb, 1866: 28–29. Type Species: Lucina  (Here) richthofeni Gabb, 1866: 28–29  , pl. 8, figs. 49–49b, by SD of Stoliczka (1871: 251). Remarks: Treated as a full  genus by Coan et al. (2000: 263).

Meekia Gabb, 1864b: 191  . Type Species: Meekia sella Gabb, 1864b: 191–192  , pl. 25, fig. 179, SD by Stoliczka (1871: 312).

Neaeromya Gabb, 1872c: 274  ; 1872d: 247. Type Species: Neaeromya quadrata Gabb, 1872d: 247  , pl. 10, figs. 4, 4a (mislabeled as 1a), 4b, unfigured, by monotypy.

Pachydon Gabb, 1869e: 198–199  . [Junior homonym of Pachydon von Meyer, 1838  ]. Type Species: Pachydon obliqua Gabb, 1869e: 199  , pl. 16, figs. 5–5e, by OD. Remarks: Pachydon obliquus Gabb  , according to Wesselingh (2006: 238). Woodward (1871: 104) noted “the name Pachydon  , ” wrote Mr. Conrad, “is objectionable, in consequence of its derivation being the same as Pachyodon  ; and I have been requested to substitute another” and “if naturalists object to Mr. Gabb’s name, I would suggest Anisothyris  (unequal valves) to take its place.” He then acknowledged the combination Anisothyris tenuis Gabb  [sic] and noted “it goes through several well-marked varieties, however; and, as our series comprises more than one hundred specimens, I may perhaps be allowed to rechristen it.” Woodward (1871: 105) then proposed the name A. hauxwelli  with P. tenuis Gabb & Conrad  [sic] as a synonym.

Polorthus Gabb, 1861c: 366  . Type Species: Teredo tibialis Morton 1834: 68  , pl. 9, fig. 2View FIGURE 2 [ Polorthus tibialis (Gabb)  , according to Palmer & Brann (1965: 282)]. Gabb (1872a: 259–262) further discussed this genus. See Carter (1978: 81–82) for comments concerning the taxonomic confusion about the type species of this genus.

Pseudocardium Gabb, 1866: 20–21  . Type Species: Cardium gabbii Rémond, 1863: 13  , by monotypy.

Remondia Gabb, 1869d: 270  . Type Species: Remondia furcata Gabb, 1869d: 270  , pl. 36, figs 17–17a, by monotypy.

Rhynchopterus Gabb, 1864  a: 31–32. [Junior homonym of Rhynchopterus Schrank, 1798  ]. Type Species: Rhynchopterus obesus Gabb, 1864  a: 32, pl. 5, figs. 30a–30b, by monotypy.

Turnus Gabb, 1864b: 145–146  . Type Species: Turnus plenus Gabb, 1864b: 146  , pl. 22, fig. 116 by OD.

SPECIES

abruptum ( Cardium  ) Gabb, 1860g: 302, unfigured. Near Purdy, McNairy Co., Tennessee; Cretaceous. Type

Material: Type material not located. Remarks: Species is based on a cast that Gabb (1860: 302) noted was "hardly perfect enough to figure."

abscissa  ( Schizodesma  ) Gabb, 1866: 20, pl. 4, figs. 34–34a. South of Martinez, Contra Costa Co., California; Miocene. Type Material: Holotype ANSP 4548 ( Stewart 1930: 210–211; Richards 1968: 29). Remarks: Spisula (Stereomactra) abscissa (Gabb)  , according to Stewart (1930: 210–211, pl. 16, fig. 6), who figured the holotype.

acuta  ( Leda  ) Gabb, 1872d: 255, unfigured. Dominican Republic; Miocene. Type Material: “ Type ” ANSP 2655 ( Richards 1968: 29). Remarks: According to Pilsbry & Johnson (1917: 185), Gabb’s Leda acuta  is a species distinct from Conrad’s (1832: 32) Leda acuta  . Pilsbry & Johnson (1917: 185) provided the new name Leda extrictata  for Leda acuta Gabb, 1872d  . Both species are valid.

acuticostata ( Callista  ) Gabb, 1872d: 250, unfigured. Dominican Republic; Miocene. Type Material: “ Type ” ANSP 2776View Materials ( Richards 1968: 29)  . Remarks: Pitar (Lamelliconcha) acuticosta (Gabb)  , according to Pilsbry (1922: 422–423, pl. 47, fig. 10), who figured the type.

aequalis  ( Donax  ) Gabb, 1872d: 249, unfigured. Dominican Republic; Miocene. Type Material: “ Type ” ANSP 2668View Materials ( Richards 1968: 29)  . Remarks: Pilsbry (1922: 426, text-fig. 47) figured the type.

aequalis  ( Tellina  ) Gabb, 1869b: 182–183, pl. 29, fig. 73. [Junior homonym of Tellina aequalis Deshayes, 1854  ] Martinez, Contra Costa Co., California; Martinez Group, Cretaceous. Type Material: Holotype ANSP 4362 ( Stewart 1930: 203–204; Richards 1968: 29). Remarks: “ Tellina  aequalis  , according to Stewart (1930: 203–204, pl. 2, fig. 8), who figured the holotype.

aequicostata ( Trigonia  ) Gabb, 1869b: 196, unfigured. Martinez, Contra Costa Co., California; Chico Group, Cretaceous. Type Material: Cotype ANSP 4421 ( Richards 1968: 30). Remarks: Figured in Gabb (1864b: pl. 26, fig. 198) as? Trigonia  sp. indet. Stewart (1930: 90–95, pl. 5, figs. 7–8) figured the species, but preservation is very poor; thus, assignment to genus Trigonia  should be queried. Stewart also stated that his pl. 5, fig. 7 specimen might correspond to Gabb's original specimen. Richards (1968: 30) listed this specimen a co-type.

aequilateralis  ( Venus  ) Gabb, 1869b: 184, pl. 30, fig. 76. San Diego, San Diego Co., California; so-called Cretaceous = Eocene ( Stewart 1930: 238). Type Material: Lectotype MCZ 108509 [formerly MCZ 15039View Materials] of Stewart (1930: 238, pl. 8, fig. 13); paralectotype MCZ 108510 (MCZ online database). Remarks: Pelecyora aequilateralis (Gabb)  , according to Stewart (1930: 238). Weaver (1942 [1943]: 194, pl. 104, fig. 6) reproduced Stewart’s lectotype figure.

affinis  ( Lithophagus  ) Gabb, 1861b: 327, unfigured. Green Marl, Burlington Co.(?), New Jersey; Cretaceous. Type Material: “ Type ” ANSP 18802View Materials ( Richards 1968: 30)  . Remarks: Lithodomus affinis  , according to Whitfield (1885: 66–67, pl. 17, figs. 2View FIGURE 2 –3 [same pagination and illustrations for Whitfield 1886]), who also figured the type. Lithophaga affinis (Gabb)  , according to Richards (1958c: 157–158, pl. 25, fig. 12 [internal mold]), who figured the type.

alabamense  ( Cardium  ( Trachycardium  )) Gabb, 1876b: 310, unfigured. Eufaula [= Eufala], Barbour Co., Alabama; Cretaceous ( Stephenson 1923: 295). Type Material: Holotype USNM 509 ( Stephenson 1923: 295). Remarks: New name for Cardium multiradiatum Gabb, 1866  , not G.B. Sowerby I in Darwin, 1846. Stephenson (1923: 295– 296, pl. 72, figs. 9–10a) figured the type. Granocardium (Criocardium) alabamense  , according to Rindsberg (2000).

alabamensis  ( Idonearca  ) Gabb, 1876b: 315, unfigured. White limestone of Prairie Bluff, Wilcox Co., Alabama; Cretaceous. Type Material: “Type” ANSP 18725 ( Richards 1968: 30). Remarks: Junior synonym of Idonearca capax (Conrad, 1858)  , according to Stephenson (1941: 92). alaeformis  ( Corbula  ) Gabb, 1869b: 177, pl. 29, fig. 63. Lower Lake Village, Lake Co., California; Paleocene. Type Material: MCZ 15049View Materials ( Stewart, 1930: 58), missing and presumed lost ( Moore 1983: A16); paratype UCMP 32515 (UCMP online database). Remarks: Hanna (1924: 169–170) provided an unnecessary replacement name, Leda polynominata  , for Gabb's species. Stewart (1930: 58–59, pl, 7, fig. 13) noted that Gabb’s original figure “is very likely a reconstruction of this specimen which, if better specimens of the original material are not forthcoming, will have to be selected as the lectotype.” Nuculana (Saccella) alaeformis (Gabb)  , according to Moore (1983: A15–A16) who figured UCMP 32515, which was labeled “ paratype.”

alata  ( Gari  ( Psammocola  )) Gabb, 1866: 21, pl. 5, fig. 36. East end of Kirker's Pass, Contra Costa Co., California; Pliocene. Type Material: “ Type ” UCMP ( Merriam 1895; missing ( Keen & Bentson 1944: 50). Remarks: Sanguinolaria alata (Gabb)  , according to Keen & Bentson (1944: 50). Nuttallina alata (Gabb)  , according to Moore (2003b: 8–9).

alta  ( Myophoria  ) Gabb, 1864a: 33, pl. 6, fig. 33. Dun Glen, Sierra District, Humboldt Co., Nevada; Triassic. Type Material: “ Type ” ANSP 30797 ( Richards 1968: 31). Remarks: Guineana alta (Gabb)  , according to Skwarko (1967: 59).

alta  ( Pharella  ) Gabb, 1864b: 147, pl. 22, fig. 118. Hills west of Martinez, Contra Costa Co., California; Cretaceous (Division A). Type Material: Lectotype ANSP 4557 of Saul (1989: 197, fig. 29). Remarks: “ Pharella alta  ” according to Stewart (1930: 293, pl. 5, fig. 11), who noted that his figure of the type specimen is the opposite valve from the one represented by the original figure. Adelodonaxaltus altus (Gabb)  , according to Saul (1989: 197–198, figs. 29–41), who also provided many views of this species, including the previously unphotographed lectotype (fig. 29), a "butterflied" specimen.

alticosta (? Cardita  ) Gabb, 1869d: 268, pl. 36, fig. 16. Sierra de las Conchas, near Arivechi, Sonora, Mexico; Cretaceous. Type Material: “Types?” ANSP 4750 ( Richards 1968: 31). Remarks: Junior synonym of Ludbrookia arivechensis ( Heilprin, 1891)  , according to Scott (1977: 1154–1157, pl. 1, figs. 1View FIGURE 1 –6), who figured the lectotype (ANSP 4763) and a paralectotype (ANSP 4750). Perrilliat (1989: fig. 118) reproduced Gabb's figure. Note: Gabb's name is very similar in spelling to but not equivalent to Cardita alticostata Conrad, 1833  , not Cardita alticostata d’Orbigny, 1850  , preoccupied.

altirostris ( Arca  ) Gabb, 1861b: 325, unfigured. Crosswicks, Burlington Co., New Jersey; Cretaceous. Type Material: “ Type ” ANSP 19573 ( Richards 1968: 31). Remarks: Species is based on a cast. Whitfield (1885: 82– 83, pl. 12, figs. 22–23 [same pagination and illustrations for Whitfield 1886]) figured the type specimen. Junior synonym of Arca quindecemradiata Gabb, 1860  , according to Weller (1907: 410).

amazonensis  ( Tellina  ) Gabb, 1869e: 198, pl. 16, fig. 4. Pebas, on Ambiyacu River [= Ampiyacu River], two miles above confluence with Marañon River [= Amazon River], Loreto Prov., Peru; Pebas Formation, so-called Pliocene? = Miocene ( Wesselingh 2006: 243). Type Material: Type material not located. Remarks: Anisothyris amazonensis (Gabb)  , according to Willard (1966: 66–68). Pachydon amazonensis (Gabb)  , according to Wesselingh (2006: 243).

americana  ( Gastrochaena  ) Gabb, 1860i: 393, pl. 68, fig. 20. Brown Marl, Timber Creek, boundary between Gloucester and Camden counties, New Jersey; so-called Cretaceous = Paleocene [Vincentown Formation ( Palmer & Brann 1965: 163)]. Type Material: Syntypes ANSP 13403 ( Palmer & Brann 1965: 163). Remarks: Polorthus americana (Gabb)  , according to Gabb (1861c: 367). Gabb (1872a: 259) reassigned P. americana  to the Cephalopoda  and made Polorthus  the type genus of the new family Polorthidae  as he believed that suture-like grooves separating annulations on the exterior of the tube indicated a chambered, septate conch. According to Stephenson (1937: 58) this was in error and he demonstrated that P. americana  is an external, protective calcareous tube secreted by a boring bivalve. Kummelia americana (Gabb)  , according to Stephenson (1937: 61, text figs. 1View FIGURE 1 –8). angulata  (? Chione  ) Gabb, 1864b: 213–214, pl. 32, fig. 281. West of Martinez, Contra Costa Co., California; Cretaceous (Division A). Type Material: Holotype ANSP 4386 ( Stewart 1930: 220; Richards 1968: 31, 101). Remarks: Holotype figured by Stewart (1930: 220–221, pl. 1, fig. 6). Nellita angulata (Gabb)  , according to Saul (1973: 11). Plastoholotype (without any matrix surrounding it) figured by Saul (1973: 11, pl. 2, fig. 2View FIGURE 2).

angulata  ( Leda  ) Gabb, 1860a: 95, pl. 2, fig. 12. [Junior homonym of Leda angulata d’Orbigny, 1830  ] Green Marl, Burlington Co., New Jersey; Cretaceous. Type Material: “ Type ” ANSP 18723View Materials ( Richards 1968: 32)  . Remarks: Nemodon angulatum (Gabb)  , according to Gabb (1876b: 316) and Whitfield (1885: 84–85, pl. 12, figs. 6–7 [same pagination and illustrations for Whitfield 1886]) who also figured the type. Weller (1907: 388–389, pl. 30, fig. 15) reproduced Whitfield’s type figure. Richards (1958c: 72–73, pl. 11, fig. 10) figured the type.

angulicosta  ( Trigonia  ) Gabb, 1876b: 312–313, unfigured. Pataula Creek, Clay Co., Georgia; Cretaceous. Type Material: “ Types ” ANSP ( Richards 1968: 32). Remarks: Pterotrigonia (Scabrotrigona) angulicosta (Gabb)  , according to Rindsberg (2000). Gabb’s species was used as the type species of Eufalagonia Cooper (2015: 31)  .

annulatum  ( Cardium  ( Laevicardium  )) Gabb, 1864b: 171, pl. 23, fig. 152. Curry’s, south of Martinez or Mt. Diablo, Contra Costa Co., California; Cretaceous (Division A). Type Material: Holotype ANSP 4382 ( Richards 1968: 32). Remarks: Original illustration reproduced by Gabb (1869b: 187, pl. 30, fig. 81). Thetironia annulata (Gabb)  , according to Stewart (1930: 279–280). Stewart’s figured specimen (pl. 1, fig. 8) “although smaller, agrees so well with the original figure, particularly in having the posterior dorsal region covered with matrix, that it is considered the holotype.”

antestriata ( Crassatella  ) Gabb, 1860i: 388, pl. 67, fig. 53. Wheelock, Robertson Co., Texas; Eocene = Wheelock Member, Cook Mountain Formation, Claiborne Group ( Palmer & Brann 1965: 99). Type Material: Holotype and three paratypes ANSP 13529 ( Palmer & Brann 1965: 99), four syntypes (P. Callomon pers. comm., 2017). Remarks: Holotype figured by Palmer & Brann (1965: 99, pl. 2, figs. 6–7) four syntypes (P. Callomon pers. comm., 2017).

antiqua  ( Meleagrina  ) Gabb, 1869b: 192–193, pl. 31, fig. 89. Departure Bay, Nanaimo, Vancouver Id., British Columbia, Canada; Cretaceous. Type Material: Missing ( Stewart 1930: 7).

antiqua  ( Rocellaria  ) Gabb, 1861d: 368–369, unfigured. James River, Virginia; Miocene. Type Material: Type material not located. Remarks: Dall (1898: 826) noted that Gabb’s description closely matched Gastrochaena cuneiformis Spengler, 1783  from the Pliocene/Pleistocene of the southeastern United States but did not synonymize the two species.

aperta ( Goniomya  ) Gabb, 1869f: 11, pl. 6, fig. 8. Volcano Mining District, Mineral Co., Nevada [about 30 mi. SE of Walker Lake]; Triassic or Jurassic. Type Material: Type material not located. Remarks: The two specimens upon which this species is based represent "float" material derived from both Triassic and Jurassic rocks, hence the unknown age.

appressa  ( Astarte  ) Gabb, 1869f: 12–13, pl. 5, fig. 10. Volcano Mining District, Mineral Co., Nevada [about 30 mi. SE of Walker Lake]; Triassic or Jurassic. Type Material: Type material not located. Remarks: The specimen upon which this species is based represents "float" material derived from both Triassic and Jurassic rocks, hence the unknown age. This also brings into question the validity of this species.

appressa  (Lima) Gabb, 1864b: 203, pl. 31, fig. 271. San Luis Gonzaga Ranch, Santa Clara and Merced counties, California; Cretaceous (Division A), “Chico Group.” Type Material: Holotype MCZ 12073View Materials of Stewart (1930: 126). Remarks: Type locality listed erroneously as Pt. Loma, San Diego Co., California ( Cooper 1894: 61) and Phoenix, Jackson Co., Oregon ( Anderson 1902: 31).

appressa  ( Ostrea  ) Gabb, 1869b: 203–204, pl. 34, figs. 104–104a. Eel River at Salt Creek mouth, southwest of Round Valley, Mendocino Co., California; so-called Cretaceous = Eocene? or Oligocene and Miocene ( Moore 1987: C33). Type Material: Syntype MCZ 15013View Materials ( Stewart 1930: 127–128, pl. 13, fig. 1View FIGURE 1); missing and presumed lost ( Moore 1987: C33); paratype MCZ 112951 (MCZ online database). Remarks: Stewart (1930: 127–128) noted that MCZ 15013View Materials “is about the size of the original figure and may have served as the basis of that figure, but it is not sufficiently close enough to be cited as the holotype.” Striostrea  ? appressa (Gabb)  , according to Moore (1987: C33, pl. 12, fig. 3; pl. 16, fig. 5), who reproduced Gabb’s original figures. White (1884: 291–292, pl. 39, fig. 9) reproduced Gabb’s original (1869b) figure and suggested that it is probably the same as O. idriaensis  .

appressa  (? Schizodesma  ) Gabb, 1876b: 306–307, unfigured. Pataula Creek, Clay Co., Georgia; Cretaceous. Type Material: Type material not located. Remarks: Richards (1958c: 246–247, pl. 37, fig. 8) figured the species but not the type. Cymbophora appressa (Gabb)  according to Stephenson (1923: 339). Weller (1907: 635) noted “Gabb’s type of this species has never been illustrated, but the New Jersey examples have been compared with the original specimen and their specific identity can be safely assumed.”

appressa  ( Tellina  ( Peronaea  )) Gabb, 1881c: 371, unfigured. Between Limon and Moen [= Moín], Limon Prov., Costa Rica; so-called Pliocene = Pliocene/Pleistocene Moín Formation ( Robinson 1993: 252). Type Material: Syntypes? ANSP 3421 ( Richards 1968: 32). Remarks: Dall (1900: 1028) noted that this species resembles Tellina rufescens Gmelin, 1791  .

appressum ( Cardium  ( Protocardia  )) Gabb, 1881a: 286, pl. 40, fig. 17. Pariatambo coal mine, Cajamarca Reg., Peru; so-called Jurassic = Cretaceous ( Rivera & Alleman 1974). Type Material: UNMSM (2 syntypes) ( Rivera & Alleman 1974).

approximans  (Axinaea) Gabb, 1872d: 255, unfigured. Dominican Republic; Miocene. Type Material: “ Type ” ANSP 2650View Materials ( Richards 1968: 32)  . Remarks: Glycymeris approximans (Gabb)  , according to Pilsbry (1922: 408, pl. 42, fig. 7), who figured the type.

arata  ( Meretrix  ) Gabb, 1864b: 166, pl. 30, fig. 250. Orestimba Canyon, Stanislaus Co., California; Cretaceous. Type Material: Cotype ANSP 4388 ( Richards 1968: 33), now = lectotype of Saul (1993: 969). Remarks: Callistalox arata (Gabb)  , according to Saul (1993: 969, 971, fig. 3.6–3.19), who figured the lectotype (fig. 3.8) and also according to Saul (1996: 127).

araucana  ( Mactra  ) Gabb, 1860b: 198, pl. 3, fig. 12. [Junior homonym of Mactra araucana d’Orbigny, 1846  ]. Chile; Cretaceous. Remarks: Gabb listed this species as “ M. araucana D’Orb.  sp. var.” and noted that it “differs a little from the one figured by d’Orbigny, in the Voyage de l’Astrolabe et Zélée, in being less angular anteriorly.” Homynym unnecessarily renamed Mactra gabbi  by Philippi (1887: 145).

arcaeformis ( Cardium  ) Gabb, 1869f: 11–12, pl. 3, fig. 9. Volcano Mining District, (about 30 mi. SE of Walker Lake, Mineral Co., Nevada); Triassic or Jurassic. Type Material: “ Types ” ANSP ( Richards 1968: 33). Remarks: The material upon which this species is based represents "float" material derived from both Triassic and Jurassic rocks, hence the unknown age.

argentarius ( Pecten  ) Gabb, 1881a: 293–294, pl. 41, figs. 12–12a. Hill of San Antonio, with silver mines, Morococho [= Morococha], Junín Reg., Peru; Cretaceous? Cerro de San Antonio , Arequipa Dept., Peru  ; Jurassic? Type Material: Type material not located.

ascia ( Mytilus  ) Gabb, 1864b: 183, pl. 30, fig. 259. Near Ft. Tejon, Kern Co., California; Eocene, Tejon Formation ( Moore, 1983: A62). Type Material: “Type” UCMP ( Merriam 1895); holotype UCMP 11989 ( Moore 1983: A62). Remarks: Mytilus  ( Mytilus  ?) ascia (Gabb), according to Moore (1983: A62, pl. 14, fig. 1View FIGURE 1), who figured the holotype. ashburnerii ( Mactra  ) Gabb, 1864b: 153, pl. 22, fig. 127. Texas Flat, Butte Co., California, Cretaceous. Type Material: Lectotype ANSP 4441 of Saul (1974: 1072); Richards (1968: 33) listed this specimen as a lectotype prior to it being designated as such. Stewart (1930: 212–213) suggested that the specimen be designated but did not himself. Remarks: Refigured by Gabb (1869b: 180–181, pl. 29, figs. 69–69a) as Cymbophora ashburnerii. Saul (1974: 1072) reported that the type locality is actually in the vicinity of Martinez, Contra Costa Co., Great Valley Series?; Cretaceous. Junior synonym of Mactromeris bisculpturata ( Anderson & Hanna, 1925)  , according to Moore (2003a: 9).

ashburnerii ( Tellina  ) Gabb, 1864b: 159, pl. 23, fig. 139. Pence's Ranch [= Pentz], north of Oroville, Butte Co., California; Cretaceous (Division A). Type Material: Missing ( Stewart 1930: 7).

atwoodi  ( Ostrea  ) Gabb, 1866: 33–34, pl. 10, figs. 58–58a; pl. 11, fig. 58b. San Lorenzo Creek, Monterey Co., California; Miocene or Pliocene = Miocene and Pliocene ( Moore 1987: C27). Type Material: “Type” UCMP ( Merriam 1895); holotype UCMP missing ( Keen & Bentson 1944: 74). Remarks: Ostrea (Ostrea) atwoodi Gabb  , according to Moore (1987: C28).

augusticostatus ( Pecten  ) Gabb, 1872d: 256, unfigured. Dominican Republic; Miocene. Type Material: “ Type ” ANSP 2866 ( Richards 1968: 34). Remarks: Pilsbry (1922: 412, pl. 45, figs. 7–8) figured the type. Junior synonym of Argopecten thetidis (G.B. Sowerby I, 1850)  according to Waller (2011: 56).

australis  ( Cultellus  ) Gabb, 1860b: 198, pl. 3, fig. 8. Chile; Cretaceous. Type Material: Type material not located. Remarks: Wilckens (1904: 249) described the genus Ceroniola  and designated Cultellus australis  the type species ( Saul 1989: 198).

australis  ( Pholadomya  ) Gabb, 1881a: 284, pl. 40, fig. 14. Hacienda of Macanga, La Libertad Reg., Peru; Cretaceous. Type Material: Type material not located.

barbarensis  ( Caryatis  ) Gabb, 1869a: 56, pl. 15, figs. 15–15a. Santa Barbara, Santa Barbara Co., California; Pliocene. Type Material: Holotype MCZ 108505 [formerly MCZ 15028View Materials ( Stewart 1930: 235)] (MCZ online database). Remarks: Pitar barbarensis (Gabb)  , according to Stewart (1930: 234–235).

bilirata  ( Sphenia  ) Gabb, 1861d: 369, unfigured. Santa Barbara, California; Miocene? Type Material: Holotype missing ( Keen & Bentson 1944: 108; Coan 1999: 115). Remarks: Smith (1893: 279) stated that this species may be “perhaps the young stage of Saxicava  .” Considered a synonym of Hiatella arctica (Linnaeus)  by Coan et al. (2000: 485). Because H. arctica  has never been collected in the Santa Barbara Formation, Coan (1999: 116) suggested that S. bilirata  might actually have been a Recent specimen.

blakei  ( Corbula  ) Gabb, 1864a: 29, pl. 5, fig. 24. Humboldt Mining Region, Humboldt Co., Nevada: Triassic. Type Material: Type material not located. Remarks: Smith (1914: 146, pl. 16, fig. 15) reproduced Gabb’s original figure.

blatchleyi  ( Posidonomya  ) Gabb, 1869f: 13–14, pl. 6, fig. 12. New Pass, west of Austin, Lander Co., Nevada; Triassic. Remarks: Posidonia blatchleyi (Gabb)  , according to Smith (1927: 112, pl. 104, fig. 4) who reproduced Gabb’s original figure.

bonaczyi  ( Barbatia  ) Gabb, 1872d: 254–255, unfigured. Dominican Republic; Miocene. Type Material: “ Type ” ANSP 2649View Materials ( Richards 1968: 35)  . Remarks: Arca bonaczyi (Gabb)  , according to Pilsbry (1922: 403, pl. 34, figs. 1– 2View FIGURE 1View FIGURE 2), who figured the type.

breweriana  ( Arca  ) Gabb, 1864b: 193–194, pl. 25, fig. 181. Cottonwood Creek, Shasta Co., California; Cretaceous (Division A). Type Material: Lectotype ANSP 4440 of Stewart (1930: 69–70, pl. 3, fig. 1View FIGURE 1); Richards (1968: 35). Remarks: Parallelodon (Nanonavis) brewerianus (Gabb)  , according to Reinhart (1943: 85). Nanonavis breweriana (Gabb)  , according to Saul & Squires (1998: 472). brewerii  ( Cardium  ) Gabb, 1864b: 173, pl. 24, fig. 155. Cañada de Uvas, Kern Co., California; so-called Cretaceous (Division B) = Eocene ( Anderson & Hanna 1925: 165–166). Type Material: Lectotype ANSP 4560 of Stewart (1930: 257); Richards (1968: 36). Remarks: Weaver (1942 [1943]: 153–154, pl. 104, fig. 12) reproduced Stewart’s figure. Acanthocardia (Schedocardia) brewerii brewerii (Gabb)  , according to Moore (2003a: 3–4).

brewerii  ( Ostrea  ) Gabb, 1864b: 204, pl. 26, fig. 191. Cow Creek, Shasta Co., California; Cretaceous. Type Material: “Type” UCMP ( Merriam 1895); holotype UCMP 31447 ( Stewart, 1930: 131). Remarks: According to White (1884: 293, unfigured), the type is an imperfect lower valve and Gabb's description is not satisfactory. Crassostrea brewerii (Gabb)  , according to Squires (2017: 37).

brewerii  ( Pholadomya  ) Gabb, 1864b: 152, pl. 22, fig. 123. Pence's Ranch [= Pentz], Butte Co., California; Cretaceous (Division A). Type Material: “Type” holotype UCMP ( Merriam 1895 [as Pholadomya breweri  ]); UCMP 11956 (UCMP online database). Remarks: Junior synonym of Pholadomya subelongata Meek, 1857  , according to Waring (1917: 64). Paralellodon breweriana  [sic] (Gabb), according to Imlay (1960: 180) who misspelled the species name.

brewerii  ( Pinna  ) Gabb, 1864b: 188, 234, pl. 25, figs. 175–175a. Curry's, south side Mt. Diablo, Contra Costa Co., California; Cretaceous (Division A). Type Material: “Type” UCMP ( Merriam 1895); holotype UCMP 31448 ( Stewart 1930: 133). Remarks: Packard & Jones (1965: 914, pl. 107, fig. 2View FIGURE 2) figured the holotype. However, they also inferred that the fragmentary holotype is inadequate for precise definition and that the species is better defined by Gabb’s (1869b: 195, 247, pl. 32, fig. 93) hypotype MCZ 108496 (MCZ online database) [formerly MCZ 15019View Materials] from Shasta Co. Also see hypotype ANSP 4392 of Stewart (1930: text fig. 4).

bryanii ( Ostrea  ) Gabb, 1876b: 321, unfigured. Vincentown, Burlington Co., New Jersey; so-called Cretaceous = Eocene, Vincentown Formation, according to Palmer & Brann (1965: 230). Type Material: “ Type ” ANSP 18763 ( Richards 1968: 36). Remarks: Gryphaea bryani  [sic] (Gabb), according to Whitfield (1885: 206–207, pl. 27, figs. 6–9 [same pagination and illustrations for Whitfield 1886]), who figured specimens “all from Mr. Gabb’s type series.” Ostrea bryani  , according to Palmer & Brann (1965: 230).

bulla  ( Cardium  ( Serripes  )) Gabb, 1872d: 251, unfigured. Dominican Republic; Miocene. H.E. Vokes (1989: 130) restricted the type locality to TU locality 1443, east bank of Río Yaque del Norte below López, unknown formation. Type Material: “ Type ” ANSP 2763 ( Richards 1968: 36). Remarks: Lucina bulla (Gabb)  , according to Pilsbry (1922: 417–418, pl. 46, fig. 6), who figured the type. Anodontia bulla (Gabb)  , according to H.E. Vokes (1989: 130).

burlingtonensis  ( Pecten  ) Gabb, 1860g: 304, pl. 48, fig. 25 [not fig. 26]. Brown sand, Burlington Co., New Jersey; Cretaceous. Type Material: Holotype ANSP 18756 ( Richards 1958c: 129, pl. 23, fig. 3); “type” ANSP 17856 [error] ( Richards 1968: 36). Remarks: Camptonectes burlingtonensis (Gabb)  , according to Gabb (1876b: 318). Whitfield (1885: 53–55, pl. 8, fig. 8 [same pagination and illustrations for Whitfield 1886]) who also figured the type. Camptonectes (Camptonectes) burlingtonensis (Gabb)  , according to Elder (1996: 254).

californica  ( Cyrena  ) Gabb, 1866: 26, pl. 7, fig. 45. [Homonym of Cyrena californica Prime, 1865  ]. East end of Kirker's Pass, Contra Costa Co., California; Pliocene. Type Material: ANSP 4496 is a set of four syntypes (“Dupl. types.” in Gabb’s handwriting), but does not include the figured specimen (P. Callomon pers. comm., 2017). Remarks: Gabb’s species was renamed Corbicula gabbiana  by Henderson (1920: 120). Stewart (1930: 197, pl. 14, fig. 5) noted that his figured specimen could be designated a neotype if the holotype is not found. Richards (1968: 36) misinterpreted this to mean that Stewart was actually designating a neotype. Hypotype ANSP 4496 of Stewart (1930: pl. 14, fig. 5) [= neotype ( Richards 1968: 36)].

californica  ( Tellina  ) Gabb, 1864b: 161, pl. 30, fig. 245. Marsh's, east of Mt. Diablo, Contra Costa Co., California; so-called Cretaceous = Paleocene and Eocene ( Moore 2003b: 8). Type Material: Type material missing ( Stewart 1930: 7). Remarks: Tellina  ( Cadella  ?) californica Gabb  , according to Moore (2003b: 8).

californicus  ( Pecten  ) Gabb, 1864b: 201–202, pl. 31, fig. 270. Cottonwood Creek, Shasta Co., California; Cretaceous (Division A). Type Material: Type material missing ( Stewart 1930: 7).

callopleurum  ( Cardium  ( Fragum  )) Gabb, 1881c: 375, pl. 47, fig. 77. Between Limon and Moen [= Moín], Limon Prov., Costa Rica; so-called Pliocene = Pliocene/Pleistocene Moín Formation ( Robinson 1993: 252). Type Material: “ Type ” ANSP 3439 ( Richards 1968: 37). Remarks: Trigoniocardia callopleurum (Gabb)  and a probable senior synonym of T. heredia ( Olsson, 1922)  according to H.E. Vokes (1989: 121).

cancellata ( Mercenaria  ) Gabb, 1860i: 376, pl. 67, fig. 25. Marl near Shiloh, Cumberland Co., New Jersey; Miocene. Type Material: “ Type ” ANSP 4137 ( Richards 1968: 37). Remarks: Type figured by Whitfield (1894: 68–69, pl. 12, figs. 2View FIGURE 2 –3).

cancellata ( Psephis  ) Gabb, 1881c: 373, pl. 47, fig. 74. Between Limon and Moen [= Moín], Limon Prov., Costa Rica; so-called Pliocene = Pliocene/Pleistocene Moín Formation ( Robinson 1993: 252). Type Material: “ Types ” ANSP 3425 ( Richards 1968:37). Remarks: Dall (1903: 1250) suggested that this species may be in the genus Gouldia  .

capuloides  ( Mysia  ) Gabb, 1872d: 252, unfigured. Dominican Republic; Miocene. Type Material: Holotype and paratypes ANSP 2694 ( Richards 1968: 111); ANSP 2694 is actually a set of syntypes divided into “ lectotype ” and “ paralectotypes ” neither of which were actually designated (P. Callomon, pers. com., 2017). Woodring (1982: 626) noted that the type was a single valve numbered ANSP 2694. Remarks: Mysia (Sphaerella) capuloides Gabb  , according to Pilsbry (1922: 419, figs. 44a–c), who also figured the type. Timothynus capuloides (Gabb)  , according to Woodring (1982: 626).

carinatum  ( Trapezium  ) Gabb, 1864b: 170, pl. 23, fig. 150. Texas Flat, Placer Co., California; Cretaceous (Division A). Type Material: Lectotype MCZ 15030View Materials of Stewart (1930: 174) [not found in MCZ online database]. Remarks: Trapezium (Schedotrapezium) carinatum (Gabb)  , according to Stewart (1930: 174–175). Lectotype probably borrowed from CAS by Gabb and never returned; however, had he returned the specimen, it may have been destroyed in the 1906 earthquake ( Stewart 1930: 174).

carinifera ( Corbula  ) Gabb, 1872d: 258, unfigured. Dominican Republic; Miocene. Type Material: Type material not located.

carolinensis  ( Idonearca  ) Gabb, 1876b: 314–315, unfigured. Snow Hill, Greene Co., North Carolina; Ripley Group, Cretaceous. Type Material: “ Types ” ANSP 2273 ( Richards 1968: 38). Remarks: Cuculaea carolinensis (Gabb)  , according to Stephenson (1923: 85–87, pl. 11, figs 14–16a), who figured two cotypes.

caudata  ( Crassatella  ) Gabb, 1881a: 287, pl. 40, fig. 18. Pariatambo coal mine, Cajamarca Reg., Peru; so-called Jurassic = Cretaceous ( Rivera & Alleman 1974). Type Material: UNMSM (4 syntypes) ( Rivera & Alleman 1974). Remarks: Crassatella (Crassatella) caudauta Gabb  , according to Gerhardt (1897: 107).

cerrosensis  ( Ostrea  ) Gabb, 1866: 35, pl. 11, fig. 61. Cerros Id. [= Isla Cedros], Baja California, Mexico; so-called Miocene = Pliocene and Pleistocene ( Moore 1987: C27). Type Material: Lectotype ANSP 4494 of Stewart (1930: 130–131, pl. 14, fig. 1View FIGURE 1) ( Richards 1968: 39 [as Ostrea megadon cerrosensis  ]). Remarks: Junior synonym of Ostrea megodon Hanley, 1846  , according to Moore (1987: C29).

cerrosensis  ( Pecten  ) Gabb, 1866: 32, pl. 9, figs. 55–55a. Cerros Id. [= Isla Cedros], Baja California, Mexico; socalled Miocene = Miocene and Pliocene ( Moore 1984: B56). Type Material: “Type” UCMP ( Merriam 1895); holotype UCMP 32669 ( Moore 1984: B55). Remarks: Lyropecten cerrosensis (Gabb)  , according to Woodring (1938: 32–34). Moore (1984: B55–B56, pl. 20, figs. 1View FIGURE 1, 4) figured the holotype. chiliensis ( Mactra  ) Gabb, 1860b: 198, pl. 3, fig. 5. Chile; Cretaceous. Type Material: Type material not located. Remarks: Philippi (1887: 140) noted that the figured specimen came from the Cretaceous near Talcahuano, Concepción Prov., Chile.

chiriquiensis  ( Arca  ) Gabb, 1860f: 567, unfigured. Chiriqui, Chiriqui Prov., Panama; Miocene and Pliocene. Type Material: “Types” ANSP 2724 and 3945 [actually two sets of syntypes (P. Callomon, pers. com., 2017)] ( Richards 1968: 39). Remarks: Junior synonym of A. grandis Broderip & G.B. Sowerby I, 1829  according to Gabb (1881c: 378), but not according to Reinhart (1943: 65). Scapharca chiriquiensis (Gabb)  , according to Maury (1917: 338). Pilsbry (1922: 405, pl. 40, figs. 2View FIGURE 2 –3) believed it to be a valid species and figured the holotype and paratype. Arca (Scaphara) chiriquiensis Gabb  , according to Tucker & Wilson (1932: 42). Anadara (Grandiarca) chiriquiensis chiriquensis (Gabb)  , according to Woodring (1973: 508–510).

circularis  ( Cardita  ( Cyclocardia  )) Gabb, 1881a: 288, pl. 41, figs. 3–3a. To left of road between Chonta and Quevopalco, Madre de Dios Reg., Peru; Cretaceous? [Cretaceous, according to Rivera & Alleman 1974]. Type Material: Holotype UNMSM ( Rivera & Alleman 1974).

circularis  ( Monotis  ) Gabb, 1869f: 15–16, pl. 7, figs. 14–14a. New Pass, near Austin, Lander Co., Nevada; Triassic. Type Material: Type material not located. Remarks: Pseudomonotis circularis (Gabb)  , according to Smith (1927: 120, pl. 104, fig. 5), who reproduced Gabb’s original figure.

clausa  ( Martesia  ) Gabb, 1864b: 145, pl. 22, fig. 115. Pence's Ranch [= Pentz], Butte Co., California; Cretaceous (Division A). Type Material: “Type” UCMP ( Merriam 1895); holotype UCMP 11947 ( Stewart 1930: 295). Remarks: Opertochasma clausa (Gabb)  , according to Kennedy (1974: 61). Hypotype ANSP 4484 of Stewart (1930: 295, pl. 24, fig. 2View FIGURE 2).

compacta ( Crassatella  ) Gabb, 1869b: 190, 244 pl. 30, fig. 85. Martinez Group, Martinez, Contra Costa Co., California; so-called Cretaceous = Paleocene ( Moore 1998a: 1). Type Material: Holotype ANSP 4415 ( Richards 1968: 40). Remarks: Holotype figured by Stewart (1930: 144–145, pl. 1, fig. 13).

complexicosta ( Neithea  ) Gabb, 1876b: 319, unfigured. Uniontown, Perry Co., Alabama; Cretaceous. Type Material: “ Types ” ANSP ( Richards 1968: 40).

complexicosta ( Pecten  ) Gabb, 1869b: 199, pl. 33, figs. 97–97a. Morgan Valley, south of Clear Lake, Lake Co., California; Shasta Group, Cretaceous. Type Material: Missing ( Stewart 1930: 7). Remarks: Stanton (1895: 37– 38), with regard to his own figures (pl. 2, figs. 7–9), stated that “Gabb’s figure is a restoration from these specimens” (USNM 23028 and 23102). Lyriochlamys complexicostata  [sic] (Gabb), according to Kaim et al. (2014: 426).

compsa  ( Leda  ) Gabb, 1860i: 387–388, pl. 67, fig. 57. Caldwell Co., Texas, Eocene = Stone City Beds, Stone City Bluff ( Dockery 1980: 147–148). Type Material: Holotype ANSP ( Palmer & Brann 1965: 63). Remarks: Calorhadia (Calorhadia) compsa (Gabb)  , according to Stenzel et al. (1957: 47, pl. 4, figs. 8–9, 12–14). Yoldia (Calorhadia) compsa (Gabb)  , according to Dockery (1980: 147–148).

concentrica  (Crenella) Gabb, 1864b: 186, pl. 24, fig. 169. Martinez, Contra Costa Co., California; so-called Cretaceous (Division B) = Cretaceous?, Paleocene? or Eocene?. Type Material: “Type” UCMP ( Merriam 1895 [as Stalagmium (Crenella) concentrica  ]; holotype UCMP 11985 ( Stewart 1930: 103). Remarks: Generic assignment uncertain, according to Stewart (1930: 103–104). “ Crenella ” concentrica  according to Squires & Saul (2006b: 122).

concentrica  ( Panopaea  ) Gabb, 1864b: 148, pl. 22, fig. 119. Cottonwood Creek, Butte Co., California; Cretaceous (Division A). Type Material: “Type” UCMP ( Merriam 1895 [as Homomya (Panopea) concentrica  ]); holotype UCMP 11957 ( Stewart 1930: 294). Remarks: Panopea  ? concentrica (Gabb)  , according to Stewart (1930: 294). Panope concentrica (Gabb)  , according to Anderson (1938: 123; 1958: 145).

conradi  ( Dosinia  ) Gabb, 1866: 25, pl. 5, fig. 43. San Emigdio Ranch, near Ft. Tejon, Kern Co., California; Miocene. Type Material: Type material missing ( Stewart 1930: 7; Keen & Bentson 1944: 48).

conradi  ( Isocardia  ) Gabb, 1860i: 393, pl. 68, fig. 21. Timber Creek, boundary between Gloucester and Camden counties, New Jersey; so-called Cretaceous = Vincentown Formation, Eocene ( Palmer & Brann 1965: 150)]. Type Material: “ Type ” ANSP 19600 ( Richards 1968: 41). Remarks: Opis conradi (Gabb)  , according to Gabb (1876b: 311). Isocardia conradi (Gabb)  according to Wade (1926: 87). Glossus  ? conradi (Gabb)  , according to Palmer & Brann (1965: 150).

conradiana  ( Astarte  ) Gabb, 1864b: 178–179, pl. 24, fig. 161. Texas Flat, Placer Co., California; Cretaceous. Type Material: Neotype ANSP 4402 ( Richards 1968: 41). Remarks: Crassatella conradiana (Gabb)  , according to Waring (1917: 56), who used the name Crassatellites  [now Crassatella  , according to Wingard 1993: 51]. Stewart (1930: 145–146, pl. 5, fig. 4; pl. 17, fig. 2View FIGURE 2) noted that his hypotype specimen (ANSP 4402) was the only one available and could be designated a neotype if the holotype is not found. Richards (1968: 41) misinterpreted this to mean that Stewart was actually designating a neotype.

conradiana  ( Cardita  ) Gabb, 1881c: 377, pl. 47, fig. 79. Between Limon and Moen [= Moín], Limon Prov., Costa Rica; so-called Pliocene = Pliocene/Pleistocene Moín Formation ( Robinson 1993: 252). Type Material: “ Type ” ANSP 3431 ( Richards 1968: 41). Remarks: Dall (1903: 1434) noted that this species was similar but smaller than Venericardia (Pleuromeris) tridentata Say, 1826  .

conradiana  ( Tapes  ) Gabb, 1864b: 169, pl. 32, fig. 282. Alizos Creek, near Ft. Tejon, Kern Co., California; socalled Cretaceous = Eocene ( Anderson & Hanna 1925: 163). Type Material: Holotype ANSP 4561 ( Stewart 1930: 244–245, pl. 12, fig. 3; Richards 1968: 41). Remarks: Weaver (1942 [1943]: 172–173, pl. 104, fig. 13) reproduced Stewart’s holotype figure. Callista (Microcallista) conradi (Gabb)  , according to Givens (1974: 55).

contorta ( Teredo  ( Uperotis  )) Gabb, 1861b: 323–324, unfigured. Burlington Co., New Jersey; Cretaceous. Type Material: “ Type ” ANSP 15908View Materials ( Richards 1968: 41)  . Remarks: Junior synonym of Xylophagella irregularis (Gabb)  , according to Richards (1958c: 261–263, pl. 39, fig. 17), who also figured the type.

cooperi  ( Yoldia  ) Gabb, 1865: 189–190, unfigured. Miocene to Recent. Type Material: USNM 30613 ( Moore, 1983: A25). Remarks: Gabb (1866: 31 [in part], pl. 9, fig. 54) illustrated the holotype. Also recorded from the Miocene Astoria Formation of Astoria, Oregon ( Moore 1963: 58). Yoldia (Portlandia) cooperi Gabb  , according to Weaver (1942 [1943]: 50, who reported the species from Grays Co., Washington. See Coan & Bogan (1988: 276) for details concerning this extant Californian species, now referred to as Yoldia (Kalayoldia) cooperi Gabb  , according to Moore (1983: A25) and Coan et al. (2000: 113).

cooperii ( Cardium  ) Gabb, 1864b: 172, pl. 24, figs. 154–154a. Martinez, Contra Costa Co., California; so-called Cretaceous (Division B) = Paleocene ( Moore 1998a: 4). Type Material: Lectotype ANSP 4468 of Stewart (1930: 276, pl. 8, fig. 7; Richards 1968: 41). Remarks: Junior synonym of Nemocardium linteum ( Conrad, 1855)  , according to Stewart (1930: 275–276).

cor  (Axinaea) Gabb, 1864b: 198, pl. 31, figs. 268–268a. Martinez, Contra Costa Co., California; so-called Cretaceous = Paleocene and Eocene ( Moore 1983: A55–A56). Type Material: “Type” UCMP ( Merriam, 1895 [as Pectunculus (Axinaea) cor  ]); holotype ANSP 4480 ( Stewart 1930: 73; Richards 1968: 42). Remarks: Axinaea Poli, 1791 and Pectunculus Lamarck, 1799  are objective synonyms of Glycymeris da Costa, 1778  (see Newell 1969: N267), thus various secondary junior homonyms involving Axinaea and Pectunculus  are now moot. For example, Merriam (1895) reported that Pectunculus cor (Gabb)  would be a secondary junior homonym of Pectunculus cor Lamarck, 1805  . Cossmann (1913: 64) renamed Gabb's species Axinea gabbi  . Cossmann's new name does not pertain to Glycymeris gabbii Dall, 1908  . Glycymeris cor (Gabb)  is a junior  synonym of Glycymeris perrini Dickerson (1916)  , according to Stewart (1930: 73–74) and Moore (1983: A55–A56). corbulopsis ( Thracia  ) Gabb, 1860b: 198, pl. 3, fig. 1View FIGURE 1. Chile; Cretaceous. Type Material: Type material not located. Remarks: Junior synonym of Corbula chilensis d’Orbigny, 1847  , according to Stinnesbeck (1986: 183).

crassiplica  ( Corbula  ) Gabb, 1860i: 394, pl. 68, fig. 25. From a cut on the Memphis and Charleston Railroad (= Norfolk Southern Railway), where it crosses the Tennessee-Mississippi state line; Cretaceous. Type Material: Type material not located. Remarks: Caestocorbula (Parmicorbula) crassiplica (Gabb)  , according to Akers & Akers (2002: 473).

crenulimarginata ( Ostrea  ) Gabb, 1860i: 398, pl. 68, figs. 40–41. Marl bank, two miles east of Middleton, Hardeman Co., Tennessee; so-called Cretaceous = Paleocene, Clayton Formation ( Palmer & Brann 1965: 232). Type Material: Unknown ( Palmer & Brann 1965: 232). Remarks: White (1884: 294, pl. 40, fig. 2View FIGURE 2) reproduced Gabb’s original figure.

cretacea  (? Lucina  ) Gabb, 1864b: 177, pl. 30, fig. 255. [Junior homonym of Lucina cretacea Alth, 1850  ]. Clayton to Marsh's, near Mt. Diablo, Contra Costa Co., California; so-called Cretaceous = Paleocene ( Moore 1988: D27). Type Material: Type material missing ( Stewart 1930: 7). Remarks: Diplodonta (Diplodonta) cretacea (Gabb)  , according to Moore (1988: D26, pl. 8, fig. 1View FIGURE 1), who reproduced Gabb’s original figure.

cretacea  ( Modiola  ) Gabb, 1860b: 198, pl. 3, fig. 3. [Junior homonym of Modiola cretacea Conrad, 1835  ]. Chile; Cretaceous. Type Material: “ Type ” ANSP ( Richards 1968: 42). Remarks: Philippi (1887: 203, pl. 44, fig. 11) appears to have reproduced Gabb’s figure and noted that the figured specimen came from the Cretaceous near Talcahuano, Concepción Prov., Chile. Botula cretacea (Gabb)  , according to Kleeman (1990: 116).

cretacea  (Pholas) Gabb, 1860i: 393, pl. 68, fig. 18. [Near Union Beach], Raritan Bay, [Monmouth Co.], New Jersey; Cretaceous. Type Material: “ Type ” ANSP 15875 ( Richards 1968: 42). Remarks: Supplementary description in Gabb 1861b: 324. Martesia cretacea (Gabb)  , according to Gabb (1876b: 304) and Weller (1907: 654–656). Martesia (Pholas) cretacea (Gabb)  , according to Whitfield (1885: 190).

cretacea  (? Tapes  ) Gabb, 1864b: 214, pl. 32, fig. 283. North of Coral Hollow, Alameda Co., California; Cretaceous. Type Material: Type material missing ( Stewart 1930: 7).

cretaceus ( Cultellus  ) Gabb, 1860g: 303–304, pl. 48, figs. 24a–24b [not fig. 25]. Burlington Co., New Jersey; Cretaceous. Type Material: Holotype ANSP 16325 ( Richards 1968: 42 [as Cultellus cretacea  ]). Remarks: Weller (1907: 628–629, pl. 71, figs. 1–2View FIGURE 1View FIGURE 2) reproduced Whitfield’s type figures. Siliqua cretacea (Gabb)  , according to Whitfield (1885: 186, pl. 25, figs. 9–10 [same pagination and illustrations for Whitfield 1886]), who also figured “a cast used by Mr. Gabb.” Richards (1958c: 241–242, pl. 37, fig. 4) also figured the type.

cultriformis  ( Anthonya  ) Gabb, 1864b: 182, pl. 30, figs. 236–236a. West of Martinez, Contra Costa Co., California; Cretaceous ( Stewart 1930: 148). Type Material: Lectotype ANSP 4424 of Stewart (1930: 148–149, pl. 4, fig. 5). Remarks: Anderson (1958: 10) erroneously used the spelling Anthonyia  .

cultriformis  ( Corbula  ) Gabb, 1864b: 149, pl. 22, fig. 122. West of Martinez, Contra Costa Co., California; Cretaceous (Division A). Type Material: “Type” UCMP ( Merriam 1895); lectotype UCMP 11945a of Squires & Saul (2004b: 120, fig. 48); paratype UCMP 32876 (UCMP online database). Remarks: Eosursivivas cultriformis (Gabb)  , according to Squires & Saul (2004b: 119–120) who also noted that the exact type locality is unknown.

cumulata  ( Lucina  ) Gabb, 1864b: 176, pl. 24, fig. 254. Near Ft. Tejon, Kern Co., California; so-called Cretaceous = Eocene ( Anderson & Hanna 1925: 171). Type Material: “Type” UCMP ( Merriam 1895); holotyp e UCMP 11988 ( Moore 1988: D88). Remarks: Divaricella cumulata (Gabb)  , according to Anderson & Hanna (1925: 171). Divaricella  ? ( Egracina  ?) cumulata (Gabb)  , according to Moore (1988: D22, pl. 7, fig. 6) who also figured the holotype. cuneata  ( Crassatella  ) Gabb, 1861e: 112 [see pteropsis  , Crassatella  ], unfigured. [Junior homonym of Crassatella cuneata Lamarck, 1818  ). Hardeman Co., Tennessee; Cretaceous Ripley Group. Type Material: “Type” USNM 553 ( Richards 1958c: 186). Remarks: Crassatellites cuneatus (Gabb)  , according to Richards (1958c: 185–186). This species name was erected by Gabb (1861e) because Crassatella pteropsis Gabb, 1860  i was a primary junior homonym of Crassatella pteropsis Conrad, 1860  . Safford (1864: 368), who was unaware that Gabb already renamed the junior homonym, renamed it as Crassatella gabbi  . Safford's invalid name was based on the same original species description and type (see Wingard 1993: 59–60, for a thorough discussion). Specimens of Crassatella cuneata  are specifically indeterminable because they are molds and casts ( Wingard 1993: 60).

cuneata  ( Trigonarca  ) Gabb, 1876b: 316–317, unfigured. Pataula Creek, Clay Co., Georgia; Cretaceous. Type Material: “ Types ” ANSP 18800 ( Richards 1968: 43). Remarks: Weller (1907: 406, pl. 30, fig. 17) figured the species but not the type, as did Richards (1958c: 84, pl. 13, figs. 14, 15). Breviarca cuneata (Gabb)  , according to Richards (1958c: 84–85).

cuneatus  ( Solen  ( Hypogella  ) ) Gabb, 1869b: 175–176, pl. 29, fig. 61. Martinez Group, Martinez, Contra Costa Co., California; Cretaceous. Type Material: Holotype ANSP 4358 ( Stewart 1930: 292; Richards 1968: 43). Remarks: " Solen  " cuneatus Gabb  , according to Stewart (1930: 292, pl. 5, fig. 12), who also figured the holotype.

cylindrica  ( Modiola  ) Gabb, 1864b: 185, pl. 25, fig. 167. [Junior homonym of Modiola cylindrica Krauss, 1848  ]. Pence's Ranch (= Pentz), Butte Co., California; Cretaceous (Division A). Type Material: “Type” UCMP ( Merriam 1895); cotype ANSP 4396View Materials ( Richards 1968: 43)  ; holotype UCMP 11961View Materials ( UCMP online database). Remarks: Gabb's homonym renamed as Volsella telea  by Stewart (1930: 99, pl. 4, fig. 7) using “duplicate type” of Gabb 1864b [= holotype ANSP 4396View Materials]  .

daytonensis  ( Posidonomya  ) Gabb, 1864a: 32–33, pl. 6, fig. 32. El Dorado Canyon, near Dayton, Lyon Co., Nevada; Triassic. Type Material: “ Type ” ANSP 30799 ( Richards 1968: 44). Remarks: Posidonia daytonensis (Gabb)  , according to Smith (1927: 112, pl. 104, fig. 4) who reproduced Gabb’s original figure.

declive  ( Cardium  ( Trachycardium  )) Gabb, 1881c: 374–375, pl. 47, fig. 76. Between Limon and Moen [= Moín], Limon Prov., Costa Rica; so-called Pliocene = Pliocene/Pleistocene Moín Formation ( Robinson 1993: 252). Type Material: “ Type ” ANSP 3428 ( Richards 1968: 44). Remarks: Trachycardium declive  , according to Global Names Index  (gni.globalnames.org) but without a corresponding author.

decurtata ( Arca  ) Gabb, 1864b: 195, pl. 31, fig. 265–265a. Rag Canyon, Napa Co., California; Cretaceous. Type Material: “Type” UCMP ( Merriam 1895); holotype UCMP 11987 (UCMP online database). Remarks: Junior synonym of Cucullaea (Cyphoxis) gravida (Gabb)  , according to Reinhart (1943: 85).

decurtata ( Tellina  ) Gabb, 1864b: 158–159, pl. 23, fig. 137. Pence's Ranch [= Pentz], 12 miles north of Oroville, Butte Co., California; Cretaceous (Division A). Type Material: “Type” UCMP ( Merriam 1895 [as Tellina decurta  ]); holotype UCMP 31452 ( Stewart 1930: 204). Remarks: “ Tellina  ” decurtata (Gabb), according to Stewart (1930: 204).

deformis  ( Pecten  ) Gabb, 1864a: 33–34, pl. 6, fig. 34. Robinson’s Ranch (= Gifford's), Genessee Valley, Plumas Co., California; Triassic ( Smith 1927: 121). Type Material: “ Type?” ANSP 30779 ( Richards 1968: 44). Remarks: Smith (1927: 121, pl. 104, fig. 2View FIGURE 2) reproduced Gabb’s original figure.

delawarensis  ( Crassatella  ) Gabb, 1860g: 303, pl. 48, fig. 20 [not fig. 21]. Deep Cut, Delaware and Chesapeake Canal, Delaware (Gabb, 1860g), Crosswicks, Burlington Co., New Jersey; Cretaceous ( Richards 1968: 44). Type Material: “Type” ANSP 18733 ( Richards 1968: 44). Remarks: Etea delawarensis (Gabb)  according to Richards (1958c: 177–178, pl. 31, fig. 1View FIGURE 1), who also figured the type but noted that it is from Crosswicks, Burlington Co., New Jersey. He also figured a specimen (ANSP 19833) from Chesapeake and Delaware Canal, Delaware. Wingard (1993: 59, pl. 22, figs. 10–12) figured the holotype, which is based on a specifically indeterminable internal mold of dubious locality and stratigraphic position. It is necessary, therefore, to restrict the name to just the holotype ( Wingard 1993: 59).

delawarensis  ( Dione  ) Gabb, 1860g: 302, pl. 48, fig. 18 [not fig. 19]. Delaware and Chesapeake Canal, [Maryland / Delaware], and New Jersey; Cretaceous. Type Material: Holotype ANSP 19402 ( Richards 1968: 44). Remarks: The type specimen is an internal mold ( Richards 1958c: 220). The specimen figured by Whitfield (1885: 153, pl. 22, fig. 10 [same pagination and illustrations for Whitfield 1886]) is probably Aphrodina eufaulensis ( Conrad, 1860) ( Richards, 1958c: 220)  . Gabb cited the type locality as “ Delaware and Chesapeake Canal and New Jersey,” but the ANSP type specimen is labeled New Jersey ( Richards 1958c: 220).

deltoidea ( Myalina  ) Gabb, 1859b: 297, unfigured. In coal or in the stratum of dark blue shale overlying the coal, near Ft. Belknap, Young Co., Texas; Carboniferous; Permian, according to Branson (1948: 637). Remarks: Junior synonym of Orthomyalina subquadrata (Shumard, 1855)  according to Branson (1948: 637)

dentata  ( Zirphaea  ) Gabb, 1866: 18, pl. 3, figs. 31–31a. E end of Kirker's Pass, Contra Costa Co., California; Pliocene, or possibly Miocene ( Grant & Gale 1931: 433). Type Material: “ Type ” UCMP ( Merriam 1895), but now lost, according to Stewart (1930: 7). Remarks: Zirfaea dentata (Gabb)  , according to Kennedy (1974: 29).

denticulicosta ( Ctenoides  ) Gabb, 1861b: 327, unfigured. Tennessee; Cretaceous. Type Material: Type material not located. Remarks: Lima denticulicosta (Gabb) according to Miller (1881: 74).

dichotomus ( Septifer  ) Gabb, 1864b: 186, pl. 30, fig. 261. Near Ft. Tejon, Kern Co., California; so-called Cretaceous = Eocene ( Anderson & Hanna 1925: 187). Type Material: Missing, according to Stewart (1930: 7) but Moore (1983: A68) reported that the holotype was located UCMP 11993. Remarks: Brachidontes  ? ( Brachidontes  ?) dichotomus, according to Moore (1983: A68, pl. 17, figs. 6–7), who figured the holotype.

diegoensis  ( Solen  ( Solena  )) Gabb, 1864b: 213, pl. 32, fig. 280. San Diego, San Diego Co., California; so-called Cretaceous = Eocene ( Moore 1998b:4). Type Material: Missing, according to Stewart (1930: 7) and Moore (1998b: 4). Remarks: Assigned to the subgenus Hypogella  by Gabb (1869b: 176). Solena (Solena) diegoensis (Gabb)  , according to Moore (1998b: 4).

discoidea (? Meretrix  ) Gabb, 1881c: 372–373, pl. 47, fig. 75. Between Limon and Moen [= Moín], Limon Prov., Costa Rica; so-called Pliocene = Pliocene/Pleistocene Moín Formation ( Robinson 1993: 252). Type Material: “ Type ” ANSP 3437 ( Richards 1968: 46).

disjuncta  ( Conchocele  ) Gabb, 1866: 28, pl. 7, figs. 48–48b. Deadman Id., San Pedro, Los Angeles Co., California; so-called Miocene = Pleistocene and Recent. Type Material: “Type” UCMP ( Merriam 1895); lectotype MCZ 15017View Materials of Stewart (1930: 195, pl. 15, fig. 1View FIGURE 1). Remarks: Weaver (1942 [1943]: 143, pl. 104, fig 1View FIGURE 1) reproduced Stewart’s figure. Moore (1988: D24–D25, pl. 7, figs. 19, 22) reproduced Gabb’s original figures. Junior synonym of Conchocele bisecta (Conrad, 1849)  , according to Coan et al. (2000: 277).

distorta  ( Nucula  ) Gabb, 1860i: 396–397, pl. 68, fig. 34. Ripley Group, Mississippi-Tennessee state line; Cretaceous. Type Material: Type material not located.

dolabraeformis  ( Neaera  ) Gabb, 1864b: 153, pl. 22, fig. 125. East of Martinez, Contra Costa Co., California; socalled Cretaceous (Division B) = Eocene ( Stewart 1930: 308–309). Type Material: “Type” UCMP ( Merriam 1895); holotype UCMP 11991 (UCMP online database). Remarks: Cardiomya dolabraeformis (Gabb)  , according to Stewart (1930: 308–309), who noted that his hypotype (ANSP 4473) was likely part of the original type lot and available to be designated as a lectotype if necessary.

dominicense  ( Cardium  ( Trachycardium  )) Gabb, 1872d: 250–251, unfigured. Dominican Republic; Miocene. Type Material: ANSP 2764 ( Pilsbry 1922); holotype according to H.E. Vokes (1989: 107). Remarks: Trachycardium 

(Dallocardia) dominicense (Gabb)  , according to H.E. Vokes (1989: 107) and Trachycardium (Dallocardia) dominicense dominicense (Gabb)  , according to Woodring (1982: 638–639). Type figured by Pilsbry (1922: 421, pl. 25, figs. 8–9).

dominicensis  ( Corbula  ) Gabb, 1872d: 247, unfigured. Dominican Republic; Miocene. Type locality designated by Anderson (1996: 14) as NMB locality 17281, López section, Río Yaque del Norte, Dominican Republic, Baitoa Formation (upper lower to lower middle Miocene). Type Material: Lectotype ANSP 2691 of Pilsbry (1922: 427); lost according to Anderson (1996: 14). Remarks: Cotypes figured by Pilsbry (1922: 427, pl. 46, figs. 12–13). Corbula (Caryocorbula) dominicensis (Gabb)  , according to Anderson (1996: 14).

d'orbignyanus ( Venus  ) Gabb, 1860b: 198, pl. 3, fig. 2View FIGURE 2. Chile; Cretaceous. Type Material: Type material not located. Remarks: Junior synonym of Venus hallii Gabb, 1861e: 178  , according to Philippi (1887: 118, pl. 14, fig. 2View FIGURE 2). Venus halli Gabb  , according to Wilckens (1904: 246).

dubia  (? Halobia  ) Gabb, 1864a: 30–31, pl. 5, figs. 28–28a. Star Canyon, Buena Vista District, Humboldt Co., Nevada; Triassic. Type Material: Lectotype ANSP 30785 of Silbering (1962: 153) [20785 in Silberling & Nichols (1982: pl. 36 caption)]. ANSP 30785 is correct and the specimen is currently missing (P. Callomon, pers. comm., 2017). Remarks: Junior synonym of Halobia (Daonella) lommeli Wissmann, 1841  , according to Meek (1877: 100). Daonella dubia (Gabb)  , according to Silbering (1962: 153). Silberling & Nichols (1982: 68, pl. 36, fig. 10) figured the lectotype.

dubia  (? Loripes  ) Gabb, 1864b: 177 [not p. 127], pl. 24 [not pl. 74], figs. 170–170b, 171. Texas Flat, Placer Co., California; Cretaceous (Division A). Type Material: Syntype ANSP 4403 ( Stewart 1930: 189–190, pl. 1, fig. 14; Richards 1968: 47). Remarks: Clisocolus dubius (Gabb)  , according to Gabb (1869b: 189).

eccentricus  ( Pecten  ) Gabb, 1872d: 256, unfigured. Dominican Republic; Miocene. Type Material: “Type” ANSP 2854 ( Richards 1968: 50 as Pecten excentricus  ) [= lectotype of Pilsbry (?) 1922: 412–413, pl. 45, fig. 12). Remarks: Argopecten eccentricus eccentricus (Gabb)  , according to Waller (2011: 42–49).

edentula  (? Siliquaria  ) Gabb, 1869a: 53, pl. 15, fig. 11. San Fernando, Los Angeles Co., California; Pliocene [Pico Formation?]. Type Material: Lectotype MCZ 108520 [formerly 15035 ( Stewart 1930: 281)] (MCZ online database). Remarks: Gari edentula (Gabb)  , according to Stewart (1930: 281–282, pl. 13, fig. 3), who figured a specimen that “agrees very well with the original dimensions and because it was labeled by Gabb, it is quite likely that it is the holotype, assuming the original figure to have been reconstructed.” Gabb's species is also recorded from the Miocene Astoria Formation of Astoria, Oregon ( Moore 1963: 82). Junior synonym of Gari (Gobraeus) fucata (Hinds, 1845)  , according to Coan et al. (2000: 426), who reported G. (G.) fucata  as extant and ranging from Santa Cruz Id., California Channel Islands to Bahía Magdalena, Baja California, Mexico.

elevata  ( Dosinia  ) Gabb, 1864b: 167, pl. 30, fig. 252. Near Ft. Tejon, Kern Co., California; so-called Cretaceous = Eocene ( Anderson & Hanna 1925: 163–164). Type Material: Lectotype ANSP 4463 of Stewart (1930: 228–229, pl. 12, fig. 1View FIGURE 1; pl. 17, fig. 8) ( Richards 1968: 48). Remarks: Cyclinella elevata (Gabb)  , according to Stewart (1930: 227–229).

elliotii ( Inoceramus  ) Gabb, 1869b: 193, pl. 31, fig. 90a. Alcatraz Id., San Francisco Bay, San Francisco Co., California; Cretaceous. Type Material: Unknown, although Stewart (1930: 106) notes that Gabb’s original figured specimen was recognized by Merriam (1895) from the UCMP collection, it is not included in his list. Remarks: Figured specimen of Stewart (1930: 106, pl. 2, fig. 2View FIGURE 2, ANSP 4411) is from Gabb’s original material but was not designated as a lectotype as “it seems quite likely that Gabb had better specimens."

elliptica  ( Anatina  ) Gabb, 1861b: 324, unfigured. [Junior homonym of Anatina elliptica King, 1832  ]. Mullica Hill, Gloucester Co., New Jersey; Cretaceous. Type Material: “ Type ” ANSP 18767View Materials ( Richards 1968: 49)  . Remarks: Periploma elliptica (Gabb)  , according to Gabb (1877: 305). Richards (1958c: 164–165, pl. 26, fig. 7) figured the type.

elliptica  ( Gari  ) Gabb, 1876b: 307–308, unfigured. Pataula Creek, Clay Co., Georgia; Cretaceous, Ripley Marl. Type Material: “ Type ” ANSP ( Richards 1968: 49). Remarks: Gari  (?) elliptica  , according to Harris (1894: 11).

elongata  (? Thetis  ) Gabb, 1869b: 186, pl. 30, figs. 80–80a. Cottonwood Creek, Shasta Co., California; Cretaceous (Chico or Shasta Group). Type Material: Lectotype ANSP 8389 of Stewart (1930: 280, pl. 1, fig. 2View FIGURE 2) [= “types” ANSP 4389 of Richards (1968: 48)]. ANSP 4389 is correct, which is a lot of seven syntypes none of which match Stewart’s lectotype and may be missing (P. Callomon, pers. comm., 2017). Remarks: "? Thetis  " elongata Gabb  , according to Stewart (1930: 280).

ephippioides ( Anomia  ) Gabb, 1860i: 388, pl. 67, fig. 59. Wheelock, Robertson Co., Texas; so-called Cretaceous = Eocene, Stone City beds ( Palmer & Brann 1965: 30). Type Material: “ Types ” ANSP 2719 (nine specimens) ( Palmer & Brann 1965: 30; Richards 1968: 49).

erringtoni  (Lima) Gabb, 1864c: 173, unfigured. Bear Valley, Mariposa Co., California: Jurassic? Type Material: Type material not located. Remarks: Meek (1865: 479, pl. 1, figs. 2–2aView FIGURE 2, 3, 5–5d) figured material of Aucella erringtoni (Gabb)  , that he believed to be Gabb’s Lima erringtoni  . There is some confusion, however, with regard to which of Meek’s figures actually pertain to Gabb’s species. Buchia erringtoni (Gabb)  , according to Crickmay (1933: pl. 16, figs. 9–12 caption), who cited hypotype USNM 7831. A variant of the Late Jurassic Buchia (Anaucella) concentrica (J. de C. Sowerby, 1827)  , according to Poulton et al. (1988: 108, pl. 53, figs. 19–20), who reported Gabb's bivalve in western Canada.

eufalensis  ( Arca  ( Macrodon  )) Gabb, 1860i: 398, pl. 68, fig. 38. Ripley Group, Eufala [= Eufaula], Barbour Co., Alabama; Cretaceous. Type Material: “ Type ” ANSP 18799 ( Richards 1968: 50, as Arca eufaulensis  ). Remarks: Nemodon eufaulensis (Gabb)  , according to Richards (1958c: 70, pl. 11, fig. 9) who also figured the type. Original spelling of Gabb is correct as eufalensis  but was emended as eufaulensis  by Whitfield (1885: 83) and Richards (1958c: 70).

eufalensis  ( Corbula  ) Gabb, 1860i: 394, pl. 68, fig. 26. Ripley Group, Eufala [= Eufaula], Barbour Co., Alabama; Cretaceous. Type Material: Type material not located. Remarks: An invalid name, according to Wingard (1993: 63). Confusion resulted as Gabb (1860: 394–395) cited Corbula eufalensis  as C. eufalensis  under the heading Corbula  , but the facing page contains the Crassatella  descriptions.

eufalensis  ( Nucula  ) Gabb, 1860i:397, pl. 68, fig. 35. Ripley Group, Eufala [= Eufaula], Barbour Co., Alabama; Cretaceous. Type Material: Holotype ANSP 30730 ( Richards 1968: 49). Remarks: Junior synonym of Nucula perequalis Conrad, 1860  according to Stephenson (1941: 72).

eufalensis  ( Trigonia  ) Gabb, 1860i: 396, pl. 68, fig. 32. Eufala [= Eufaula], Barbour Co., Alabama; Cretaceous. Type Material: “ Type ” ANSP 19578 ( Richards 1968: 49). Remarks: Trigonia eufaulensis  , according to Richards (1958c: 123–124). The original spelling of Gabb is correct as eufalensis  but was emended as eufaulensis  by Whitfield (1886: 83), Stephenson (1923: 112; 1955: 189), and Richards (1958c: 49). Pterotrigonia (Scabrotrigonia) eufalensis (Gabb)  , according to Rindsberg (2000). Gabb’s species was used as the type species of Gabbigonia Cooper (2015: 31)  .

euryterma ( Tellina  ) Gabb, 1861d: 369, unfigured. Vicksburg, Waren Co., Mississippi; so-called Eocene = Oligocene ( Dockery 1982). Type Material: “ Type ” ANSP ( Richards 1968: 50).

exogyrella ( Ostrea  ) Gabb, 1876b: 322–323, unfigured. Pataula Creek, Clay Co., Georgia; Cretaceous. Type Material: Type material not located. Remarks: White (1884: 296) noted Gabb’s lack of an illustration and regarding his description stated “he reported it from the Cretaceous strata of Georgia, but so far as I am aware it has not been since recognized.” fragilis  (? Meretrix  ) Gabb, 1869b: 185, pl. 30, fig. 77. Martinez, Contra Costa Co., California; Martinez Group = Cretaceous, Saul (1993: 971). Type Material: “Type” ANSP 4385 ( Richards 1968: 52) = lectotype of Stewart (1930: 247, pl. 4, fig. 4 [as “? Meretrix  fragilis  ]). Remarks: “? Meretrix  fragilis Gabb  , according to Stewart (1930: 247) and Saul 1993: fig. 3.20 [in fig. caption only]. Callistolax fragilis (Gabb)  , according to Saul (1993: 971).

furcata  ( Remondia  ) Gabb, 1869d: 270–271, pl. 36, figs. 17–17a. Sierra de las Conchas, near Arivechi, Sonora, Mexico; Cretaceous. Type Material: “ Types ” ANSP 4762 ( Richards 1968: 52). Remarks: Stanton (1897: pl. 26, figs. 2View FIGURE 2 –5) figured the type material. Perrilliat (1989: 359, fig. 136j) reproduced Gabb's figure 17.

gambrina ( Protocardia  ) Gabb, 1861d: 371, unfigured. Texas [Houston Co. ( Palmer & Brann 1965: 204)]; Eocene = Cook Mountain Formation ( Palmer & Brann 1965: 204). Type Material: Holotype ANSP 3957 ( Palmer & Brann 1965: 204, pl. 1, figs. 6, 10; Richards 1968: 52, as “type”). Remarks: Nemocardium gambrinum (Gabb)  , according to Palmer & Brann (1965: 204).

georgiana  ( Peronaeoderma  ) Gabb, 1876b: 308, unfigured. Pataula Creek, Clay Co., Georgia; Cretaceous. Type Material: “ Type ” ANSP 18792 ( Richards 1968: 53). Remarks: Weller (1907: 617), and restated by Richards (1958c: 230–231), suggested that this species might actually belong in the genus Tellina  but hesitated because the name Tellina georgiana  was preoccupied by Tellina georgiana (Gabb, 1876)  . Gardner (1916: 694–695) proposed the new name Tellina (Arcopagia) gabbi  .

georgiana  ( Tellina  ( Tellinella  ) ) Gabb, 1876b: 307, unfigured. Pataula Creek, Clay Co., Georgia; Cretaceous. Type Material: “ Type ” ANSP 18791 ( Richards 1968: 53). Remarks: Assigned to the subgenus Arcopagia  by Gardner (1916: 692). “ Tellina  georgiana Gabb  , according to Rindsberg (2000).

gibbosa ( Mysia  ) Gabb, 1860g: 302, pl. 48, fig. 17 [not fig. 18]. Delaware and Chesapeake Canal, and New Jersey; Cretaceous. Type Material: “ Type ” ANSP 18746 ( Richards 1968: 138). Remarks: Junior synonym of Tenea pinguis ( Conrad, 1860)  , according to Johnson (1905: 15) and Richards (1958c: 219–220).

gibbosa ( Raeta  ) Gabb, 1869g: 30, unfigured. Payta [= Paita], Piura Dept., Peru; Tertiary. Tablazo beds (late Pliocene or early Pleistocene) ( Olsson, 1932: 133). Type Material: Not at ANSP ( Olsson 1932: 133). Remarks: Figured in Gabb, 1881a, pl. 35, figs. 8–8a. Junior synonym of Labiosa (Raeta) undulata Gould, 1851  , according to Olsson (1932: 131–133).

gibbosus ( Saxidomus  ) Gabb, 1869a: 58, pl. 16, figs. 18–18b. Eagle Prairie, Humboldt Co., California; Pliocene. Type Material: Lectotype MCZ 15044View Materials of Stewart (1930: 225, pl. 14, fig. 6). Remarks: Junior synonym of Compsomyax subdiaphana (Carpenter, 1864)  , according to Coan et al. (2000: 377).

grandicosta  ( Neithea  ) Gabb, 1869b: 200, pl. 33, fig. 99a. Cottonwood Creek, Shasta Co., California; Shasta Group, Cretaceous. Type Material: Paratype ANSP 4435 ( Richards 1968: 53) [= lectotype of Stewart 1930: 116, pl. 1, fig. 5]. Remarks: Neithea (Neitheops) grandicosta (Gabb)  , according to Stewart (1930: 116). Neithea (Neithea) grandicosta Gabb  , according to Iba et al. (2011: 64–65).

grandis  ( Crassatella  ) Gabb, 1864b: 181, pl. 24, fig. 163. Near Ft. Tejon, Kern Co., California ( Stewart 1930: 143); so-called Cretaceous = Eocene ( Anderson & Hanna 1925: 172–173). Type Material: Lectotype UCMP 31449 of Stewart (1930: 142); “types” ANSP 4452 ( Richards 1968: 54); paratype UCMP 12510 (UCMP online database). Remarks: Cited by Gabb (1869b: 189–190). Junior synonym of Crassatella uvasana Conrad, 1855  , according to Stewart (1930: 142) and Squires (1984: 47–49). Gabb figured hypotype ANSP 4461, which was also figured by Stewart (1930: 142, pl. 12, fig. 9), who identified it as Crassatella uvasana Conrad, 1855  .

granuliferum ( Cardium  ( Protocardium  )) Gabb, 1869d: 267–268, pl. 36, fig. 15. Sierra de las Conchas, near Arivechi, Sonora, Mexico; Cretaceous. Type Material: “ Types ” ANSP 4748 ( Richards 1968: 54 as Cardium 

granuliferum). Remarks: Protocardium  (P.) granuliferum (Gabb), according to Almanzan-Vazquez (1990). Perrilliat (1989: 313, fig. 118f) reproduced Gabb's original figure.

gravida  ( Arca  ) Gabb, 1864b: 194–195, pl. 30, fig. 264. San Luis Gonzaga Ranch, Pacheco Pass, Santa Clara Co., California; Cretaceous (Division A). Type Material: “Type” UCMP ( Merriam 1895); cotype? ANSP 4405 ( Richards 1968: 54); holotype UCMP 11952 and paratype UCMP 11293 (UCMP online database). Remarks: Cucullaea (Cyphoxis) gravida (Gabb)  , according to Reinhart (1943: 85). Cucullaea (Idonearca) gravida (Gabb)  , according to Saul (1996: 127).

guppyana  ( Caryatis  ) Gabb, 1881c: 373–374, pl. 47, fig. 73. Between Limon and Moen [= Moín], Limon Prov., Costa Rica; so-called Pliocene = Pliocene/Pleistocene ( Robinson 1993: 252). Type Material: ANSP 3454 ( Richards 1968: 54). Remarks: Pitaria guppyana (Gabb)  , according to Olsson (1922: 237–238).

guppyana  ( Chione  ) Gabb, 1872d: 249, unfigured. Dominican Republic; Miocene. Type Material: “ Type ” ANSP 2773 ( Richards 1968: 54). Remarks: Pilsbry (1922: 423, pl. 47, figs. 3–5) figured the type. Chione (Chione) guppyana Gabb  , according to Perrilliat (1984: 11, pl. 9, figs. 7, 8).

gyrata  ( Dosinia  ) Gabb, 1864b: 168, pl. 23, fig. 148. Marsh's, southeast of Mt. Diablo, Contra Costa Co., California; so-called Cretaceous = Eocene ( Moore 1988: D20–D21). Type Material: “Type” UCMP ( Merriam 1895 [as Dosina gyrata  ]; Clark & Woodford 1927: 93); holotype UCMP 11986 ( Moore 1988: D20, pl. 7, fig. 1View FIGURE 1); paratype UCMP 12411 (UCMP online database). Remarks: Phacoides gyrata (Gabb)  , according to Clark & Woodford (1927: 93). Miltha (Eomiltha) gyrata (Gabb)  , according to Stewart (1930: 192–193). Gibbolucina (Eomiltha) gyrata (Gabb)  , according to Moore (1988: D20). Hypotype of Stewart (1930) [ANSP 4469 = lectotype of Richards (1968: 54), which is a misinterpretation of Stewart] (pl. 12, fig. 11) is probably one of the original type lot.

hallii  ( Venus  ) Gabb, 1861e: 178, unfigured. Chili [ Chile]; Cretaceous. Type Material: Type material not located. Remarks: Philippi (1887: 118, pl. 14, fig. 2View FIGURE 2) refigured Gabb’s original illustration. Venus halli Gabb  , according to Wilckens (1904: 246).

hoffmanniana  ( Tellina  ) Gabb, 1864b: 156–157, pl. 22, figs. 133–133a. West of Martinez, Contra Costa Co., California; Cretaceous (Division A). Type Material: “Type lot” ANSP 4384 ( Richards 1968: 55). Remarks: Figured by Gabb (1869b: 182, pl. 30, fig. 72) but is missing according to Stewart (1930: 201–202). “ Tellina  hoffmanniana  according to Stewart (1930: 201–202, pl. 6, fig. 12). Stewart’s figure “is the best of 12 in the Academy’s collection.” He went on to note that none of those specimens sufficiently corresponds to either of the original figures to be considered a holotype but any could be designated as a lectotype. Stewart also noted that the Museum of Paleontology has nine specimens labeled “ Tellina hoffmanniana  G.” in Gabb’s handwriting, but none can be cited as any of his figured specimens.

homfrayi  (Avicula) Gabb, 1864a: 29–30, pl. 6, fig. 26. Star District, Humboldt Co., Nevada; Triassic. Type Material: Type material not located.

homfrayi  ( Mytilus  ) Gabb, 1864a: 29, pl. 6, fig. 25. Dun Glen, Sierra District, Humboldt Co., Nevada; Triassic. Type Material: Type material not located.

hornii  ( Arca  ) Gabb, 1864b: 194, pl. 30, fig. 263. Near Ft. Tejon, Kern Co., California; so-called Cretaceous = Eocene ( Moore 1983: A48–A49). Type Material: “Type” UCMP ( Merriam 1895 [as Arca horni  ]); holotype ANSP 4460 ( Stewart 1930: 79–80, pl. 10, fig. 6) [= paratype, according to Richards (1968: 55)]; missing, according to Moore (1983: A48); paratypes UCMP 12134, 14771 (UCMP online database). Remarks: Pachecoa (Pachecoa) hornii (Gabb)  , according to Moore (1983: A48–A49). hornii  ( Cardita  ) Gabb, 1864b: 174, pl. 24, fig. 157. Near Ft. Tejon [Live Oak Canyon, see Moore 1992: E23], Kern Co., California; so-called Cretaceous = Eocene ( Moore 1992: E23). Type Material: Lectotype ANSP 4558 of Stewart (1930: 165–168, pl. 11, fig. 1View FIGURE 1); [= “type” according to Richards (1968: 55)]. Remarks: Specimen figured by Gabb (1869b: 187–188, pl. 30, fig. 83a) prior to lectotype designation. Venericardia (Pacificor) hornii (Gabb)  , according to Moore (1992: E23). Gabb (1869b: 187–188, pl. 30, fig. 83a).

hornii  ( Corbula  ) Gabb, 1864b: 149–150, pl. 29, fig. 238. Near Ft. Tejon, Kern Co., California; so-called Cretaceous = Eocene ( Anderson & Hanna 1925: 128). Type Material: Holotype ANSP 4459 ( Richards 1968: 55). Remarks: Corbula (Caryocorbula) hornii Gabb  , according to Stewart (1930: 287–288, pl. 12, figs. 4–5). Figured by Gabb (1869b: 176, pl. 29, figs. 62–62b).

hornii  ( Meretrix  ) Gabb, 1864b: 164, pl. 23, fig. 144. Near Ft. Tejon, Kern Co., California; so-called Cretaceous = Eocene ( Anderson & Hanna 1925: 158). Type Material: Lectotype ANSP 4454 of Stewart (1930: 243) ( Richards, 1968: 55, pl. 12., fig. 8). Remarks: Figured in Gabb (1869b: 185, pl. 30, fig. 78). Macrocallista  ( Costacallista  ?) hornii (Gabb)  , according to Givens (1974: 55).

hornii  ( Tellina  ) Gabb, 1864b: 160–161, pl. 30, fig. 244. Near Ft. Tejon, Kern Co., California; so-called Cretaceous (Division B) = Eocene ( Anderson & Hanna 1925: 151–152). Type Material: Lectotype ANSP 4453 of Stewart (1930: 282–283, pl. 12, fig. 2View FIGURE 2) ( Richards 1968: 55). Remarks: Gari hornii (Gabb)  , according to Stewart (1930: 282–283, pl. 12, fig. 2View FIGURE 2).

hubbardii  ( Unio  ) Gabb, 1869b: 190–191, pl. 30, fig. 86. Nanaimo Coal Mine, Vancouver Id., British Columbia, Canada; Chico Group, Cretaceous. Type Material: Type material missing ( Stewart 1930: 7). Remarks: Whiteaves (1901: 177) cited that the type is actually from Graham Id., Queen Charlotte Ids., British Columbia, Canada. Elliptio hubbardi (Gabb)  , according to Russell (1934: 2) and Elliptio hubbardii (Gabb)  , according to Modell (1957: 187).

humboldtensis  ( Myacites  ( Panopaea  ?)) Gabb, 1864a: 28, pl. 5, fig. 22. Buena Vista District, Humboldt Mining Region, Nevada; Triassic. Type Material: Type material not located. Remarks: Pleuromya humboldtensis (Gabb)  , according to Smith (1914: 143, pl. 16, fig. 14), who reproduced Gabb’s original figure.

idriaensis  ( Ostrea  ) Gabb, 1869b: 203, pl. 33, figs. 103b–103d, pl. 34, figs. 103–103a. East of Hacienda at New Idira, San Benito Co., California; so-called Cretaceous = Eocene ( Moore 1987: C31). Type Material: Lectotype MCZ 15048View Materials of Stewart (1930: 127, pl. 8, fig. 3, pl. 17, fig. 1View FIGURE 1). Remarks: White (1884: 296, pl. 39 [not pl. 34], fig. 8) reproduced Gabb’s original figure as did H.E. Vokes (1935: 291–295, pl. 22, fig. 3–7) and Moore (1987: C31– C32, pl. 13 figs. 2View FIGURE 2 –3, pl. 14, fig. 6, pl. 16, fig. 4, pl. 29, fig. 4). Acutostrea idriaensis idriaensis (Gabb)  , according to Moore (1987: C31–C32). Acutostrea idriaensis (Gabb)  , according to Squires (2018: 4).

inconspicua  ( Pteria  ) Gabb, 1881a: 290, pl. 41, fig. 5. Pariatambo coal mine, Cajamarca Reg., Peru; so-called Liassic = Cretaceous ( Rivera & Alleman 1974). Type Material: Holotype UNMSM ( Rivera & Alleman 1974). Remarks: Pteria (Avicula) inconspicua Gabb  , according to Gerhardt (1897: 116).

inconspicua  ( Pandora  ) Gabb, 1872d: 248, unfigured. Dominican Republic; Miocene; presumably Cercado Formation ( Woodring 1982: 721). Type Material: Holotype and paratypes ANSP 2676 ( Richards 1968: 57 [in error]); lectotype of Pilsbry (1922: 414), according to Woodring (1982: 721). No holotype was selected (P. Callomon, pers. comm. 2017). The ANSP database notes that the lot was split and Pilsbry’s lectotype retains ANSP 2676. Pilsbry’s figured paralectotype (and nine other paralectotypes) were recataloged as ANSP 79199 (P. Callomon, pers. comm. 2017). Remarks: Pilsbry (1922: 414, pl. 38, figs. 8–9) figured the “type and paratype ” [= paralectotype]. Pandora (Pandorella) inconspicua (Gabb)  , according to Woodring (1982: 721).

incrassatus  ( Kuphus  ) Gabb, 1872d: 246, unfigured. Valley of Río Yaque del Norte, east of Guayubín, Provincia de Monte Cristo, Dominican Republic; Miocene. Type Material: “ Types ” ANSP 2785 ( Richards 1968: 57). Remarks: Teredo incrassatus (Gabb)  , according to Pilsbry (1922: 428). Type figured by Gabb (1881b: 342, pl. 44, figs. 12–12e). Kuphus  incrassatus Gabb  ,” according to Woodring (1982: 719–720), who used quotation marks to indicate a tentative identification of the species.

incurva ( Homomya  ) Gabb, 1881a: 285–286, pl. 40, figs. 13–13a. Near Ollon (= Oyón), Lima Reg., Peru; Jurassic or Cretaceous. Type Material: Type material not located.

incurva ( Lithophaga  ) Gabb, 1881c: 377, pl. 47, fig. 80. Between Limon and Moen [= Moín], Limon Prov., Costa Rica; so-called Pliocene = Pliocene/Pleistocene ( Robinson 1993: 252). Type Material: Paratypes ANSP 3447 ( Richards 1968: 57).

inequilaterialis  ( Anatina  ) Gabb, 1864b: 151, pl. 21, fig. 241. Near the stage road, north side Siskiyou Mountains, Klamath and Jackson counties, Oregon; Cretaceous (Division A). Type Material: Holotype ANSP 4366 ( Richards 1968: 57). Remarks: Periplomya inequilaterialis (Gabb)  , according to Stewart (1930: 298).

inermis  ( Cucullaea  ) Gabb, 1869d: 271–272, pl. 36, fig. 18. Sierra de las Conchas, near Arivechi, Sonora, Mexico; Cretaceous. Type Material: “ Types ” ANSP 4757 ( Richards 1968: 57). Remarks: Cucullaea (Idonearca) inermis Gabb  , according to Almazan-Vazquez (1990: pl. 3, figs. 8–8b) and Scott (2007: 11). Perrilliat (1989: 319, fig. 121a) reproduced Gabb's figure.

inflata  ( Dosinia  ) Gabb, 1864b: 168, pl. 23, fig. 149. Chico Creek, Butte Co., California; Cretaceous (Division A). Type Material: “Type” UCMP ( Merriam 1895); holotype UCMP 31455 ( Stewart 1930: 231). Remarks: Tenea inflata (Gabb)  , according to Popenoe (1937: 391–392) and Saul (1996: 127).

inornata  (Avicula) Gabb, 1872d: 253, unfigured. Dominican Republic; Miocene. Type Material: “ Types ” ANSP 2748 ( Pilsbry 1922: 408, pl. 42, figs. 6–7; Richards 1968: 57). Remarks: Pteria inornata (Gabb)  , according to Pilsbry (1922: 408).

inornata  ( Placunanomia  ) Gabb, 1864b: 217, pl. 32, figs. 288–288a. North of Corral Hollow, Alameda Co., California; so-called Cretaceous = Eocene ( Moore, 1987: C9). Type Material: Lectotype ANSP 4442 of Stewart (1930) [error by Richards 1968: 57]; lectotype ANSP 4442 of Moore (1987: C9, pl. 6, fig. 2View FIGURE 2; pl. 7, fig. 3), who also noted that the specimen is also missing and presumed lost. Remarks: “ Placunanomia  inornata Gabb  , according to Stewart (1930: 66). Weaver (1942 [1943]: 101, pl. 104, figs. 8, 14) reproduced Stewart’s (1930: pl. 8, fig. 4) figure (as paratype). Anomia inornatus (Gabb)  , according to Moore (1987: C9).

intercostata  (Axinaea) Gabb, 1860i: 402, pl. 68, fig. 2View FIGURE 2. Alabama; so-called Eocene = Oligocene ( Palmer & Brann 1965: 152–153). Type Material: “Type” ANSP ( Richards 1968: 58); holotype ANSP 31431 ( Dockery 1982: 38, pl. 58, fig. 1View FIGURE 1). Remarks: Glycymeris intercostata (Gabb)  , according to Dall (1898: 607), Palmer & Brann (1965: 152–153, pl. 1, figs. 1–2View FIGURE 1View FIGURE 2), and Dockery (1982: 38). Tucetona (Bellaxinaea) intercostata (Gabb)  according to Nicol & Jones (1984: 127).

interlineatus  ( Pecten  ) Gabb, 1872d: 256, unfigured. Dominican Republic; Oligocene (see Tucker & Wilson 1932). Waller (2011: 32) noted that the type specimen probably came from the vicinity of TU 1245, a road cut in the Mao Adentro Limestone, just south of the bridge at Guayubín, on the road to Sabaneta, Dominican Republic, where the species is abundant and well preserved. Type Material: “Type” ANSP 2856 ( Richards 1968: 58) [ANSP 2846 according to Waller (2011: 32)]. No holotype was selected and ANSP 2846 is erroneous (P. Callomon, pers. comm., 2017). Remarks: Pilsbry (1922: 411, pl. 45, fig. 3) figured the type. Pecten (Chlamys) interlineatus Gabb  , according to Tucker & Wilson (1932: 43). Interchlamys interlineata (Gabb)  , according to Waller (2011: 31–32).

interradiatus ( Pecten  ) Gabb, 1869b: 199–200, 251, pl. 33, figs. 98–98a. East of New Idria, San Benito Co., California; so-called Cretaceous = Eocene and Oligocene ( Moore 1984: B7). Type Material: Lectotype ANSP 4652 of Stewart (1930: 123–124, pl. 8, fig. 10) [not ANSP 4442 as cited by Stewart 1930: 124 ( Moore 1984: B7)];

Richards (1968: 58). Remarks: Propeamussium interradiatum (Gabb)  , according to Moore (1984: B7, pl. 1, fig. 1View FIGURE 1), who figured the lectotype.

irregularis  ( Teredo  ) Gabb, 1860i: 393, pl. 68, fig. 19. New Jersey, Cretaceous, according to Richards (1968: 58). Type Material: “ Types ” ANSP 15900 ( Richards 1968: 58). Remarks: Whitfield (1885: 191–192, pl. 25, fig. 18) figured the type as did Richards (1958c: 261–263, pl. 39, fig. 19). Xylophagella irregularis (Gabb)  , according to Stephenson (1941: 247).

kimballi (Lima) Gabb, 1872b: 264–265, pl. 11, fig. 1View FIGURE 1. Nugal, Chihuahua, Mexico; Cretaceous. Type Material: Type material not located. Remarks: Lima kimballi Smith (1927: 122, pl. 7, fig. 6) of Late Triassic age in northern California is a homonym of Gabb’s species.

laevigata  ( Janira  ) Gabb, 1881c: 379, pl. 47, fig. 84. [Junior homonym of Janira laevigata Schumacher, 1817  ]. Between Limon and Moen [= Moín], Limon Prov., Costa Rica; so-called Pliocene = Pliocene/Pleistocene Moín Formation ( Robinson 1993: 252). Type Material: “ Types?” ANSP 3436 ( Richards 1968: 59). Remarks: Dall (1898: 713) coined the name Pecten (Euvola) limonensis  as the new name for Janira laevigata Gabb, 1881  , non Pecten laevigatus Goldfuss, 1833  (see also Boss et al. 1968: 186).

larviformis ( Ostrea  ) Gabb, 1881a: 297, pl. 42, fig. 3. Hill of three crosses, between Aguamiro and Huallacan, Ancash Reg., Peru; Cretaceous. Type Material: Type material not located. Remarks: Neumann (1904: 102, 129) noted that Gabb’s species was collected from Santonian rocks near La Quinua, Huamanga Prov. , Peru  .

lata (? Anatina  ) Gabb, 1864b: 151, pl. 22, fig. 126. Pence's Ranch [= Pentz], Butte Co., California; Cretaceous (Division A). Type Material: “Type” UCMP ( Merriam 1895); holotype UCMP 11949 ( Stewart 1930: 300). Remarks: “? Anatina  ” lata Gabb, according to Stewart (1930: 300) who also noted that “related species have not been recognized.”

latus  ( Donax  ) Gabb, 1869b: 183–184, pl. 30, fig. 75. 10 miles west of Griswold's, southeast of the Sheep Well, on the road from San Juan to New Idria, San Benito Co., California; so-called Cretaceous = Eocene ( Stewart 1930: 205). Type Material: Holotype MCZ 108506 [formerly MCZ 15028View Materials ( Stewart 1930: 205, pl. 8, fig. 5)] (MCZ online database).

leana  ( Trigonia  ) Gabb, 1876b: 312, unfigured. Near Martinez, Contra Costa Co., California; Cretaceous. Type Material: Lectotype UCMP 12131 of Merriam (1895) ( Anderson 1958: 113 [error]); [= UCMP 12171, according to Saul 1978: 34, pl. 4, fig. 1View FIGURE 1 [who erroneously reported this specimen as holotype in figure caption]), paralectotypes UCMP 14498–14499 ( Saul 1978: 34). Remarks: Gabb (1864b: 190, pl. 25, fig. 178, pl. 31, fig. 262) originally identified this species as Trigonia gibboniana Lea  ?, [1840], which he described as a new species in 1876 but did not refigure the type. Saul (1978: 33–39, pl. 4, fig. 1View FIGURE 1) noted that when Gabb proposed T. leana  as a new name for specimens he earlier called T. gibboniana  that Merriam’s (1895) listing construed as the earliest designation of a lectotype. Yaadia leana (Gabb)  , according to Saul (1978: 33–39).

lens  ( Meretrix  ) Gabb, 1864b: 164, pl. 23, fig. 143. Chico Creek, Butte Co., California; Cretaceous (Division A). Type Material: “Type lot” ANSP 4387 ( Richards 1968: 60). Remarks: Paraesa  ? lens (Gabb)  , according to Saul (1993: 976). The figured specimen of Stewart (1930: 247–248, pl. 4, fig. 6) is smaller than the original figured specimen and he chose not to designate a lectotype.

lenticularis  ( Hemimactra  ) Gabb, 1866: 19, pl. 4, fig. 33. South of Martinez, Contra Costa Co., California; Miocene, San Ramon Formation ( Moore 2003a: 15). Type Material: Lectotype ANSP 4549 of Stewart (1930: 208–209, pl. 16, fig. 4; Richards 1968: 60). Remarks: Mactromeris catilliformis lenticularis (Gabb)  , according to Moore (2003a: 15). lenticularis  ( Venus  ) Gabb, 1864b: 162, pl. 30, fig. 246. [Junior homonym of Venus lenticularis Broderip & G.B. Sowerby I, 1835  ]. Benicia, Solano Co., California; Cretaceous. Type Material: Holotype ANSP 4393 ( Richards 1968: 60). Remarks: “ Venus  lenticularis Gabb  , according to Stewart (1930: 219). He also noted that “this specimen may be the adult of “ Venus  veatchii  . These two species will be placed under Eriphyla  if the “duplicate type” of E. umbonata  is correctly determined.” Eurhomalea lenticularis (Broderip & Sowerby I, 1835)  , according to Huber (2010: 373) in MolluscaBase (2015) accessed through WoRMS (marinespecies.org).

lima ( Placunanomia  ( Paranomia  ?)) Gabb, 1881a: 296, pl. 42, fig. 7. Near Ollon (= Oyón), Lima Reg., Peru; Cretaceous. Type Material: Type material not located.

limonensis  ( Nucula  ) Gabb, 1881c: 378–379, pl. 47, fig. 82. Between Limon and Moen [= Moín], Limon Prov., Costa Rica; so-called Pliocene = Pliocene/Pleistocene Moín Formation ( Robinson 1993: 252). Type Material: “ Type ” ANSP 3114 ( Richards 1968: 61).

lineata  ( Anomia  ) Gabb, 1864b: 203–204, pl. 26, fig. 193. [Junior homonym of Anomia lineata  J. de. C. Sowerby, 1825), not A. lineata Brown, 1845  ]. Pence's Ranch [= Pentz], Butte Co., California; Cretaceous (Division A). Type Material: Holotype UCMP 11950 ( Stewart 1930: 65); paratype? ANSP 4398 ( Richards 1968: 61). Remarks: Stewart (1930: 65) noted that this species closely resembles A. linensis Whiteaves, 1900  from the Cretaceous of Line Id., British Columbia, Canada and may be conspecific.

lineatus  ( Tagelus  ) Gabb, 1881c: 370, pl. 47, fig. 71. Between Limon and Moen (= Moin), Limon Prov., Costa Rica; so-called Pliocene = Pliocene/Pleistocene ( Robinson 1993: 252). Type Material: “ Type ” ANSP 3443 ( Richards 1968: 61). Remarks: Junior synonym of Psammosolen cumingianus (Dunker, 1861)  , according to Dall (1900: 961).

lingulata ( Cassianella  ) Gabb, 1869f: 14–15, pl. 7 [not pl. 5 as in text], figs. 13–13b. Star Canyon, Pershing Co., Nevada; so-called Jurassic = Late Triassic ( McRoberts & Blodgett 2000: 58). Remarks: McRoberts & Blodgett (2000: 58) noted that this species is well known from Upper Triassic (Rhaetian) rocks of west-central Nevada and also common in the Cadwaller terrane of British Columbia, Canada.

littlei  ( Idonearca  ) Gabb, 1876b: 316, unfigured. Pataula Creek, Clay Co., Georgia; Cretaceous. Type Material: “ Type ” ANSP 18764 ( Richards 1968: 62). Remarks: Cucullaea littlei (Gabb)  according to Wade (1926: 45, pl. 9, fig. 5). Cucullaea (Idonearca) littlei (Gabb)  , according to Rindsberg (2000).

littlei  ( Ostrea  ) Gabb, 1876b: 321–322, unfigured. Pataula Creek, Clay Co., Georgia; Cretaceous. Type Material: ANSP ( Richards 1968: 62). Remarks: Turkostrea littlei (Gabb)  , according to Rindsberg (2000).

littlei  ( Pholadomya  ) Gabb, 1876b: 305–306, unfigured. Pataula Creek, Clay Co., Georgia; Cretaceous. Type Material: “ Types ” ANSP 2274 ( Richards 1968: 62). Remarks: Stephenson (1923: 247–249, pl. 64, figs. 1–2View FIGURE 1View FIGURE 2, pl. 65, fig. 10) figured two cotypes.

longa  ( Meretrix  ) Gabb, 1864b: 165, pl. 23, fig. 147. "Shasta," California; Cretaceous. Type Material: “Type” UCMP ( Merriam 1895); holotype UCMP 31454 ( Stewart 1930: 247). Remarks: " Meretrix  " longa Gabb  , according to Stewart (1930: 247), who stated that the type locality is likely Texas Flat, Placer Co., California.

longa  ( Tellina  ) Gabb, 1864b: 155–156, pl. 22, fig. 131. Near Martinez, Contra Costa Co., California; so called Cretaceous (Division B) = Paleocene and Eocene ( Moore 2003b: 4). Type Material: Holotype (missing) and paratype MCZ 15037View Materials, according to Moore (2003b: 4); Remarks: Tellina  ( Angulus  ?) longa Gabb  , according to Moore (2003b: pl. 1, figs. 6a, b).

lordlyi ( Caryatis  ) Gabb, 1881c: 373, unfigured. Between Limon and Moen [= Moín], Limon Prov., Costa Rica; socalled Pliocene = Pliocene/Pleistocene ( Robinson 1993: 252). Type Material: Holotype ANSP 3414 ( Richards 1968: 62). lyonii (Pluronectia) Gabb, 1881b: 347, pl. 45, figs. 25a–b. Rio Reventazon, Sapote, Limon Prov., Costa Rica; Miocene. Type Material: Holotype and paratypes ANSP 3476 ( Richards 1968: 63). No holotype was selected and ANSP 3458, 3459, and 3476 are all syntypes (P. Callomon, pers. comm., 2017). Remarks: Amusium lyoni (Gabb)  , according to Mongin (1968: 475–476).

major  ( Modiolus  ) Gabb, 1869b: 191–192, pl. 31, fig. 88. East of Knoxville, Lake Co. [Napa Co.], California; Shasta Group, Cretaceous. Type Material: Holotype? MCZ 15015View Materials ( Stewart 1930: 104, pl. 4, fig. 1View FIGURE 1 [see remarks]); lectotype MCZ 108539 of Jenkins et al. (2013: 362–365, figs. 5–6 [= Gabb’s type]), paralectotypes MCZ 10538View Materials, 108540. Remarks: Myoconcha major (Gabb)  , according to Stewart (1930: 104). He also noted that his figured specimen ( MCZ 15015View Materials) “is probably the holotype ” but because all of the original material had not been examined it is figured “as an example” of the species. Capsiconcha major (Gabb)  , according to Kiel et al. (2010: 37, 43) and Jenkins et al. (2013: 362–365, figs. 5–6).

malleiformis  ( Ostrea  ) Gabb, 1864b: 204, pl. 31, fig. 272. Cottonwood Creek, Shasta Co., California; Cretaceous (Division A) “Chico Group.” Type Material: Neotype ANSP 4433 of Stewart (1930: 131, pl. 3, fig. 10, text fig. 3) [erroneously listed as lectotype by Richards 1968: 63]. Remarks: White (1884: 297, pl. 50, fig 7 [not fig. 8] reproduced Gabb’s original figure. " Ostrea  " malleiformis Gabb  , according to Stewart (1930: 131). Pycnodonte (Pycnodonte) malleiformis (Gabb)  , according to Squires (2017: 45).

martinezensis  ( Pecten  ) Gabb, 1869b: 198–199, pl. 33, fig. 96. Martinez, Contra Costa Co., California; so-called Cretaceous = Paleocene ( Moore 1984: B9). Type Material: Lectotype MCZ 108502 [formerly MCZ 15026View Materials a of Stewart (1930: 117, pl. 7, fig. 10)]; (MCZ 108502, online database); paralectotypes MCZ 108503–108504. Remarks: Cyclopecten  ? martinezensis (Gabb)  , according to Moore (1984: B8–B9, pl. 1, figs. 9–10), who figured the lectotype (fig. 9 [ MCZ 15026View Materials a]) and a paralectotype (fig. 10 [ MCZ 15026View Materials, = MCZ 108503, on-line catalog] as paratype).

mathewsonii  ( Astarte  ) Gabb, 1864b: 179, pl. 30, fig. 258. Near Martinez, Contra Costa Co., California; so-called Cretaceous = Eocene ( Keen & Bentson 1944: 30). Type Material: Holotype ANSP 4563 ( Richards 1968: 64). Remarks: Crassatella uvasana mathewsonii (Gabb)  , according to Stewart (1930: 143–144, pl. 8, fig. 9), who figured the holotype. Junior synonym of Crassatella uvasana (Gabb)  , according to Squires (1984: 47–49).

mathewsonii  ( Chione  ) Gabb, 1866: 23, pl. 5, fig. 39. South of Martinez, Contra Costa Co., California; so-called Cretaceous = Miocene ( Stewart 1930). Type Material: Lectotype ANSP 4532 of Stewart (1930: 245–246, pl. 14, fig. 2View FIGURE 2) ( Richards 1968: 64). Remarks: Amiantis  ? mathewsonii (Gabb)  according to Stewart (1930: 245–246). Amiantis mathewsoni (Gabb)  , according to Addicott (1973: 35).

mathewsonii  ( Cucullaea  ) Gabb, 1864b: 195–196, pl. 31, fig. 266. Martinez, Contra Costa Co., California; socalled Cretaceous = Paleocene and Eocene ( Moore 1983: A47). Type Material: Lectotype ANSP 4559 of Stewart (1930: 77–78, pl. 8, fig. 8) ( Richards 1968: 64).

mathewsonii  ( Dosinia  ) Gabb, 1869a: 57, pl. 15, fig. 16. Martinez, Contra Costa Co., California; Miocene. Type Material: Syntype ANSP 4485 ( Stewart 1930: 231). Remarks: Dosinia (Dosinia) mathewsonii Gabb  , according to Clark (1918: 141). Stewart (1930: 230–232) suggested that his figured specimen (pl. 14, fig. 7) be designated a lectotype if original type specimen cannot be located.

mathewsonii  ( Mytilus  ) Gabb, 1866: 30, pl. 8, fig. 51. South of Martinez, Contra Costa Co., California; Miocene = Miocene? ( Moore 1983: A63). Type Material: Lectotype ANSP 4500 of Stewart (1930: 96, pl. 13, fig. 2View FIGURE 2) ( Richards 1968: 64). Remarks: Mytilus (Crenomytilus) mathewsonii Gabb  , according to Moore (1983: A63, pl. 14, fig. 6), who figured the lectotype.

mathewsonii  ( Tellina  ) Gabb, 1864b: 158, pl. 23, fig. 136. Near Martinez, Contra Costa Co., California; Cretaceous. Type Material: “Type lot”ANSP 4373 ( Richards 1968: 64); lectotype ANSP 4373 of Saul (1973: 25, pl. 1, fig.

25); paralectotypes ANSP 4373a, UCMP 10076, 47445 ( Saul 1974: 25); paratypes [= paralectotypes?] UCMP 10072–10075, 10077–10080 (UCMP online database). Remarks: “ Tellina  mathewsonii Gabb  , according to Stewart (1930: 201). Willamactra (Petromactra) mathewsonii (Gabb)  , according to Saul (1973: pl. 1, fig. 25), who figured the lectotype but mislabeled it as a paratype in plate caption.

mauricensis ( Ostrea  ) Gabb, 1860i: 376, pl. 67, fig. 26. Marl, Maurice River, New Jersey; Miocene. Type Material: “ Types ” ANSP 19527 ( Richards 1968: 64). Remarks: Junior synonym of Ostrea virginiana (Gmelin, 1791)  , according to Whitfield (1894: 27–28) who refigured Gabb’s (1860) type specimen.

meekana  ( Venus  ) Gabb, 1860i: 394, pl. 68, fig. 23. Eufala [= Eufaula], Barbour Co., Alabama; Cretaceous , Ripley Group. Type Material: Holotype USNM 551View Materials (not found in USNM online database). Remarks: Dione  (?) meekiana [sic] (Gabb), according to Marcou (1885: 48). 

meekianum  ( Cardium  ) Gabb, 1866: 27, pl. 7, fig. 46. Eagle Prairie, Humboldt Co., California; Pliocene. Type Material: Holotype ANSP 4497 ( Richards 1968: 65). Remarks: Holotype figured by Stewart (1930: 262–263, pl. 13, fig. 5) and assigned to Cerastoderma  . Clinocardium meekianum (Gabb)  , according to Kafanov (1998: 37–38, pl. 1, figs. 9–11) who also figured the holotype.

meridionalis  ( Astarte  ) Gabb, 1881c: 376, pl. 47, fig. 78. Between Limon and Moen [= Moín], Limon Prov., Costa Rica; so-called Pliocene = Pliocene/Pleistocene Moín Formation ( Robinson 1993: 252). Type Material: Holotype ANSP 3432 ( Richards 1968: 65).

microtis (Lima) Gabb, 1864b: 202, pl. 26, fig. 189. Cottonwood Creek, Shasta Co., California; Cretaceous (Division A). Type Material: Type material missing ( Stewart 1930: 7). Remarks: Stanton (1895: 36) compared this species to his new species Lima multilineata  and considered them to be distinct.

milleri ( Cardium  ( Laevicardium  )) Gabb, 1881b: 345, pl. 44, fig. 18. Sapote, Limon Prov., Costa Rica; Miocene. Type Material: “ Type?” ANSP 3478 ( Richards 1968: 65). Remarks: Dall (1900: 1111) suggested that this species may be reassigned to the genus Protocardia  .

milleri ( Nuculana  ) Gabb, 1881b: 346, pl. 44, figs. 22–22a. Sapote, Limon Prov., Costa Rica; Miocene. Type Material: “ Type ” ANSP 3484 ( Richards 1968: 65).

minuta  ( Pinna  ) Gabb, 1860b: 198, pl. 3, fig. 10. Chile; Cretaceous. Type Material: “ Type ” ANSP 31283 ( Richards 1968: 219 [as Pinna minutum  ]). Remarks: Hyatt (1891: 346) suggested that this species may belong to the genus Cyrtopinna  .

minuta  ( Tellina  ( Peronaeoderma  )) Gabb, 1872d: 249, unfigured. [Junior homonym of Tellina minuta Deshayes, 1857  ]. Dominican Republic; Miocene. Type Material: “ Type ” ANSP 2789 ( Pilsbry 1922: 424, text-figs. 46a, b; Richards 1968: 66). Remarks: Tellina minuta Gabb  , according to Pilsbry (1922: 424).

moenensis ( Donax  ) Gabb, 1881c: 371–372, pl. 47, fig. 72. Between Limon and Moen [= Moín], Limon Prov., Costa Rica; so-called Pliocene = Pliocene/Pleistocene Moín Formation ( Robinson 1993: 252). Type Material: Holotype and paratype ANSP 3108 ( Richards 1968: 67). No holotype was selected and ANSP 3018 is a syntype (P. Callomon, pers. comm., 2017).

moenensis ( Nucula  ) Gabb, 1881c: 379, pl. 47, fig. 83. Between Limon and Moen (= Moin), Limon Prov., Costa Rica; so-called Pliocene = Pliocene/Pleistocene Moín Formation ( Robinson 1993: 252). Type Material: “ Type ” ANSP 3115 ( Richards 1968: 67).

monilicosta ( Cardita  ) Gabb, 1861d: 371, unfigured. Santa Barbara, California; Miocene? Santa Barbara Formation, Pleistocene ( Moore 1992: E13). Type Material: Unknown ( Moore 1992: E13). Remarks: Junior synonym of Cyclocardia (Cyclocardia) occidentalis ( Conrad 1855)  , according to Moore (1992: E13). monilifera ( Tellina  ) Gabb, 1864b: 157, pl. 22, figs. 134–134a. Texas Flat, Placer Co., California; Cretaceous (Division A). Type Material: “Type” UCMP ( Merriam 1895); lectotype UCMP 11964 of Stewart (1930: 284). Remarks: Agnomyax monilifer (Gabb)  , according to Stewart (1930: 283–284, pl. 17, fig. 9).

monmouthensis ( Crassatella  ) Gabb, 1860g: 302–303, pl. 48, fig. 19 [not fig. 20]. Monmouth and Burlington counties, New Jersey; Cretaceous. Type Material: “ Type ” ANSP 18738 ( Richards 1968: 67). Remarks: Junior synonym of Veniella (Etea) trapezoidea Conrad, 1860  , according to Richards (1958c: 175–177, pl. 29, fig.15), who figured the type. The type is based on specifically indeterminable molds and probably belongs to genus Etea  , not Crassatella  , according to Wingard (1993: 58, pl. 22, figs. 7–9), who also figured the type.

mooreana  ( Tellina  ) Gabb, 1860i: 387, pl. 67, fig. 56. Caldwell Co. [Burleson Co. ( Palmer & Brann 1965: 307)], Texas; Eocene,Weches Formation, Claiborne Group ( Palmer & Brann 1965: 307). Type Material: “ Type ” ANSP 13260 ( Richards 1968: 67). Remarks: Assigned to subgenus Eurytellina  by Stenzel et al. (1957: 121).

mooreana  ( Trigonia  ) Gabb, 1861e: 176, unfigured. Texas; Cretaceous. Type Material: Type material not located ( Scott 2007: 28). Remarks: New name for T. crenulata Roemer, 1852  [not T. crenulata Lamarck, 1819  ], according to Heilprin (1890: 452). Scabrotrigonia mooreana (Gabb)  , according to Scott (2007: 28).

moorei  ( Posidonia  ) Gabb, 1859b: 297, unfigured. From buff colored limestone above the coal, near Ft. Belknap, Young Co., Texas; Carboniferous or Permian ( Richards 1968: 67). Type Material: “ Type ” ANSP [missing] ( Richards 1968: 67). Remarks: Astarella moorei (Gabb)  , according to Newell (1937: 37) and Branson (1948: 569).

morsei  ( Barbatia  ) Gabb, 1864b: 216, pl. 32, fig. 286. San Diego, San Diego Co., California; so-called Cretaceous = Eocene ( Moore, 1983). Type Material: “Type” UCMP ( Merriam 1895); holotype UCMP 11984 ( Weaver 1942 [1943]: 70 [UCMP online database]); lectotype of Reinhart (1943: 31) ( Moore 1983: A34). Remarks: Stewart (1930: 87) noted that Merriam doubtfully recognized Gabb’s original type but that it should be in the UCMP collection. Reinhart (1943: 30–31) designated UCMP 11984 as the lectotype based on Stewart’s notation from Merriam (1895). Richards (1968: 67) interpreted this to mean that Stewart designated ANSP 4447 as a lectotype and mistakenly credited Stewart for this designation. Barbatia (Obliquarca) morsei Gabb  , according to Reinhart (1943: 30) and Weaver (1942 [1943]: 69–70). Barbatia (Barbatia) morsei Gabb  , according to Moore (1983: A34, pl. 5, fig. 7) who figured the lectotype. Weaver (1942 [1943]: 69–70, pl. 12, fig. 4) reproduced Gabb’s original figure.

mortoni  ( Neithea  ) Gabb, 1861c: 365, unfigured. New Jersey, Cretaceous. Type Material: Type material not located. Remarks: Junior synonym of Pecten quinquecostatus (J. Sowerby, 1814)  , according to Wade (1926: 64, pl. 21, figs. 1View FIGURE 1 –5).

mortoni  ( Ostrea  ) Gabb, 1861b: 329, unfigured. South Carolina; Eocene, Santee Limestone, upper Claiborne Group ( Palmer & Brann 1965: 27). Type Material: Holotype and possible paratypes ANSP 31407 ( Richards 1968: 67). No holotype was selected and ANSP 31407 includes three syntypes (P. Callomon, pers. comm. 2017). Remarks: Junior synonym of Ostrea panda Morton, 1833  , according to White (1884: 311). Alectryonia vicksburgensis mortoni (Gabb)  , according to Palmer & Brann (1965: 26–27).

mucronata  (Avicula) Gabb, 1864a: 30, pl. 5, fig. 27. Gifford's Ranch, Genesee Valley, Plumas Co., California; Swearinger Slate; Triassic. Type Material: “ Type lot” ANSP 30788 ( Richards 1968: 67). Remarks: Smith (1927: 111–112, pl. 104, fig. 1View FIGURE 1) reproduced Gabb’s original figure. Pteria mucronata (Gabb)  , according to Squires (2014b: 219) as Avicula and Pteria  are objective synonyms.

mucronata  ( Gryphaea  ) Gabb, 1869d: 274–275, unfigured. [Junior homonym of Gryphaea mucronata Lamarck, 1801  ]. Sierra de las Conchas, Arivechi, Sonora, Mexico; Cretaceous, Potrero Formation ( Stanton 1947: pl. 18, caption). Type Material: ANSP 4773, four cotypes ( Stanton 1947: 28). Remarks: White (1884: 302) noted that this species name, which was proposed by Gabb “for the variety of G. pitcheri  to which Conrad had previously given the name G. navia  ” was an unnecessary new name. Stanton (1947: 28, pl. 18, figs. 1View FIGURE 1 –18) figured the cotypes. multicostata  ( Asaphis  ) Gabb, 1869b: 181, pl. 29, fig. 70. Crooked Creek of the Deschutes River, central Oregon; Cretaceous, “Chico Group.” Type Material: “ Type ” ANSP 4369 ( Richards 1968: 67). Remarks: Linearia multicostata (Gabb)  , according to Stewart (1930: 284–285, pl. 4, figs. 8–9).

multilineata  ( Arca  ) Gabb, 1872d: 254, unfigured. Dominican Republic; Miocene. Type Material: “Type” and paratype ANSP 2652 ( Richards 1968: 67). ANSP 2652 lot was split and Pilsbry (1922: 407) designated a lectotype and three paralectotypes, which have been cataloged as ANSP 79120 (P. Callomon, pers. comm. 2017). Remarks: Pilsbry (1922: 407, pl. 42, figs. 13–14) figured the type.

multilineata  ( Pholadomya  ) Gabb, 1869f: 10, pl. 5, fig. 6. Volcano Mining District, Mineral Co., Nevada [about 30 mi. SE of Walker Lake]; Triassic or Jurassic. Type Material: Whitney Collection, MCZ ( Hyatt 1894: 419); holotype MCZ 109971 (MCZ online database). Remarks: The material upon which this species is based represents "float" material derived from both Triassic and Jurassic rocks.

multiradiata  ( Cibota  ) Gabb, 1860a: 95, pl. 2, fig. 1View FIGURE 1. Green Marl, Mullica Hill, Gloucester Co., New Jersey; Cretaceous. Type Material: “ Type ” ANSP 19574 ( Richards 1968: 68). Remarks: Whitfield (1885: 94, pl. 11, figs. 21–22 [same pagination and illustrations for Whitfield 1886]) reproduced Gabb’s original figure. Junior synonym of Arca quindecemradiata Gabb, 1860  , according to Weller (1907: 410).

multiradiata  (Lima) Gabb, 1869b: 201–202, pl. 33, fig. 101. Lower Lake Village, Lake Co., California; so-called Cretaceous = Paleocene and Eocene ( Moore 1987: C15). Type Material: Holotype MCZ 108547 [formerly MCZ 15016View Materials ( Stewart 1930: 125–126, text fig. 2View FIGURE 2] (MCZ online database). Remarks: Acesta (Acesta) multiradiata (Gabb)  , according to Moore (1987: C14–C15, pl. 10, fig. 8), who reproduced Gabb’s original figure.

multiradiata  ( Modiola  ) Gabb, 1866: 30, pl. 8, fig. 52. Martinez, Contra Costa Co., California ( Stewart 1930: 97); so-called Miocene = Paleocene ( Moore 1983: A69). Type Material: “Type” UCMP ( Merriam 1895); holotype ANSP 4482 ( Stewart 1930: 96–97, pl. 14, fig. 3; Richards 1968: 68). Remarks: Brachidontes  ? ( Scolimytilus  ?) multiradiatus (Gabb), according to Moore (1983: A69, pl. 17, figs. 12, 17), who figured the holotype.

multiradiatum  ( Cardium  ) Gabb, 1860i: 395, pl. 68, fig. 29. [Junior homonym of Cardium multiradiatum G.B. Sowerby I, in Darwin 1846  ]. Ripley Group, Eufala, [= Eufaula], Barbour Co., Alabama; Cretaceous. Type Material: Holotype USNM 509 (not in on-line catalog). Remarks: Gabb (1876b: 310) renamed his own homonym as Cardium (Trachycardium) alabamense Gabb. 

nasuta  ( Lucina  ) Gabb, 1864b: 175, pl. 24, fig. 159 [not fig. 158, according to Gabb 1869b: 189]. Near Martinez, Contra Costa Co., California; so-called Cretaceous (Division A) = Eocene ( Moore 1988: D23). Type Material: Holotype ANSP 4465 ( Stewart 1930: 182–183, pl. 7, fig. 4); ANSP 4475 ( Richards 1968: 68 [error]). Remarks: " Lucina  " nasuta Gabb  , according to Stewart (1930: 182–183) who suggested that this species is probably a tellinid. Moore (1988: pl. 5, fig.10) also figured the holotype but erroneously noted that it is from the Tejon Formation in the plate caption.

nasuta  ( Pholadomya  ) Gabb, 1864b: 152, pl. 30, fig. 124. Shore of Straits of Carquines, west of Martinez, Contra Costa Co., California; so-called Cretaceous (Division A) = Paleocene ( Zinsmeister 1978: 233). Type Material: “Type” UCMP ( Merriam 1895); “type” ANSP 4562 ( Richards 1968: 68); paratype UCMP 11958 (UCMP online database). Remarks: Pholadomya (Pholadomya) nasuta Gabb  , according to Zinsmeister (1978: 233).

nasuta  ( Yoldia  ) Gabb, 1864b: 216, pl. 32, fig. 287. Los Angeles, Los Angeles Co., California; so-called Cretaceous = Pleistocene (Gabb 1869a: 58). Type Material: California Academy of Sciences (Gabb 1864b: 216); missing ( Stewart 1930: 7). Remarks: Gabb (1869a: 58) stated that this species "has proven to be undoubtedly Tertiary" and "it seems to me to be more like the Post-Pliocene deposit near San Pedro [Los Angeles Co.]." Stewart (1930: 59) stated he was doubtful of any typical Yoldia  of Eocene age or older. navis (M eekia) Gabb, 1864b: 192–193, pl. 25, fig. 180. Near Martinez, Contra Costa Co., California; Cretaceous (Division A). Type Material: “Type” UCMP ( Merriam 1895); holotype UCMP 31458 ( Stewart 1930: 307); paratype UCMP 12516 (UCMP online database). Remarks: " Meekia  " navis Gabb, according to Stewart (1930: 307) and Saul & Popenoe (1962: 312–313).

neglecta  ( Cucullaea  ) Gabb, 1861b: 326, unfigured. Crosswicks, Burlington Co., New Jersey and St. Georges, New Castle Co., Delaware; Cretaceous. Type Material: Holotype ANSP 18765, paratypes ANSP 18720 ( Richards 1968: 69). Remarks: Idonearca neglecta (Gabb)  , according to Gabb (1876b: 314). Richards (1958c: 78–79, pl. 13, figs. 1View FIGURE 1, 4) figured the holotype.

nevadana ( Pholadomya  ) Gabb, 1869f: 10, pl. 5, fig. 7. Volcano Mining District, Mineral Co., Nevada [about 30 mi. SE of Walker Lake]; Triassic or Jurassic. Remarks: The material upon which this species is based represents "float" material derived from both Triassic and Jurassic rocks.

newberryanum ( Cardium  ( Protocardia  )) Gabb, 1881b: 344, pl. 44, fig. 17. Gatun, Colon Prov., Panama; Miocene. Type Material: Holotype ANSP 3514 ( Richards 1968: 69 [also listed as Cardium newberryi  ]). Remarks: Woodring (1982: 644) noted that despite Gabb’s claim, the specimen was from Gatun and is “doubtless a Protocardia  from an unknown Upper Cretaceous locality.”

newcombiana  ( Circe  (Lioconcha )) Gabb, 1865: 189, unfigured. Miocene to Recent. Type Material: Type specimen label located at UCMP but not specimen, according to Coan & Bogan (1988: 276). Remarks: See Coan & Bogan (1988: 276) for details concerning this extant Californian species, now referred to as Pitar (Pitar) newcombianus (Gabb)  , according to Coan et al. (2000: 380).

nitida  ( Meretrix  ) Gabb, 1864b: 165, pl. 23, figs. 145–146. Near Martinez, Contra Costa Co., California; Cretaceous (Division A). Type Material: “Type lot” ANSP 4374 ( Richards 1968: 69); lectotype ANSP 4374 of Saul & Popenoe (1992: 29). Remarks: Calva (Egelicalva) nitida (Gabb)  , according to Saul & Popenoe (1992: 27–31).

nuculoides  ( Corbula  ) Gabb, 1881a: 283, pl. 40, fig. 10. Pariatamba coal mine, Cajamarca Reg., Peru; so-called Liassic = Cretaceous ( Rivera & Alleman 1974). Type Material: UNMSM (5 syntypes) ( Rivera & Alleman 1974). Remarks: Perissonota nuculoides (Gabb)  , according to Gerhardt (1897: 100). Nucula nuculoides Gabb  , according to Willard (1966: 55) [this is a misprint and should be Corbula nuculoides  ].

obesus  ( Rhynchopterus  ) Gabb, 1864a: 32, pl. 5, figs. 30a–30b. Rattlesnake Pt., near Humboldt City, Humboldt Co., Nevada; Triassic. Type Material: Holotype ANSP 30791 ( Richards 1968: 28). Remarks: Smith (1914: 145, pl. 16, figs. 16–17) reproduced Gabb’s original figures. Pteria  ? obesus (Gabb)  , according to Silberling & Nichols (1982: 66, pl. 38, figs. 8–9), who figured the holotype.

obliqua  ( Pachydon  ) Gabb, 1869e: 199, pl. 16, figs. 5–5e. Pebas, on Ambiyacu River [= Ampiyacu River], two miles above confluence with Marañon River [= Amazon River], Loreto Prov., Peru; Pebas Formation; so-called Pliocene? = Miocene ( Wesselingh 2006: 238). Type Material: Type material not located. Remarks: Anisothyris (Pachydon) obliqua Gabb  , according to Woodward (1871: 106). Pachydon obliquus  [sic] Gabb, according to Wesselingh (2006: 238). See remarks under the genus Pachydon  (herein).

occidentalis  (? Hemimactra  ) Gabb, 1869a: 54–55, pl. 15, figs. 13–13a. South of Martinez, Contra Costa Co., California; Miocene, San Ramon Formation ( Moore 2003a: 14). Type Material: Holotype and paratype ANSP 4545 ( Richards 1968: 70). Holotype ANSP 4545 was confirmed from the figure; another specimen formerly in ANSP 4545 was split out as it is another taxon, but cataloged in error (P. Callomon, pers. comm. 2017). Remarks: Spisula (Mactromeris) occidentalis (Gabb)  , according to Stewart (1930: 209–210, pl. 15, fig. 5), who figured the holotype. Mactromeris occidentalis (Gabb)  , according to Moore (2003a: 13–14). octolirata  ( Astarte  ) Gabb, 1860i: 394–395, pl. 68, fig. 27. Ripley Group, Eufala [= Eufaula], Barbour Co., Alabama; Cretaceous. Type Material: Type material not located. Remarks: Verticordia octolirata (Gabb)  , according to Whitfield (1885: 127 [same pagination for Whitfield 1886]).

ooides  ( Tellina  ) Gabb, 1864b: 157–158, pl. 22, figs. 135–135a. West of Martinez, Contra Costa Co., California; Cretaceous. Type Material: “Type” UCMP ( Merriam 1895); lectotype UCMP 12072 of Stewart (1930: 203); syntype [= paralectotype?] UCMP 31437 (UCMP online database). Remarks: Legumen ooides (Gabb)  , according to Popenoe (1937: 394).

operculiformis  ( Pecten  ) Gabb, 1864b: 201, pl. 26, fig. 188. Cottonwood and Huling Creeks, Shasta Co., California; Cretaceous (Division A). Type Material: Lectotype UCMP 31446 of Stewart (1930: 120–121); paratypes UCMP 11295–11296, 12508, 14115 [= paralectotypes?] (UCMP online database). Remarks: Syncyclonema operculiformis Gabb  , according to Stewart (1930: 120–121).

orbiculata  ( Pholadomya  ) Gabb, 1864c: 173, unfigured. [Junior homonym of Pholadomya orbiculata Roemer, 1836  ]. Bear Valley, Mariposa Co., California; Jurassic? Type Material: CAS? Remarks: Meek (1865: 481, pl. 1, fig. 4) figured a specimen of Pholadomya  [?] orbiculata Gabb  , that he believed to be equivalent to Gabb’s Pholadomya orbiculata  .

orbignyana  ( Trigonarca  ) Gabb, 1881a: 290–291, pl. 41, figs. 7–7a, 8–8a. Near Ollon (= Oyón), Lima Reg., Peru; Jurassic or Cretaceous. Type Material: Type material not located. Remarks: Age probably Late Jurassic, according to Olsson (1934: 26).

oregonensis  ( Pholadomya  ) Gabb, 1869b: 178, pl. 29, fig. 65. Near the Toll House at the summit of Siskiyou Mountains, Jackson and Klamath counties, Oregon; Cretaceous (“Chico Group”). Type Material: “ Type ” ANSP 4367 ( Stewart 1930: 302, pl. 3, fig. 11; Richards 1968: 70).

oregonensis  ( Siliqua  ) Gabb, 1864b: 147, pl. 29, fig. 237. Near the toll house on the stage road, north side of Siskiyou Mountains, Jackson and Klamath counties, Oregon; Cretaceous. Type Material: Holotype ANSP 4365 ( Stewart 1930: 300, pl. 5, fig. 3; Richards 1968: 70). Remarks: Periplomya  ? oregonensis (Gabb)  , according to Stewart (1930: 300). “ Periplomya  oregonensis (Gabb)  , according to Anderson (1958: 119).

ornata  ( Anomia  argentaria var.) Gabb, 1876b: 320, unfigured. Pataula Creek, Clay Co., Georgia: Cretaceous. Type Material: “ Types ” ANSP ( Richards 1968: 71). Remarks: Anomia ornata (Gabb)  , according to Gardner (1916: 612).

ornata  ( Modiola  ) Gabb, 1864b: 184–185, pl. 24, fig. 166. Martinez, Contra Costa Co., California; so-called Cretaceous (Division B) = Paleocene to Oligocene ( Moore 1983: A66). Type Material: Lectotype ANSP 4450 of Stewart (1930: 101) ( Richards 1968: 71). Remarks: Junior synonym of Brachidontes cowlitzensis Weaver & Palmer, 1922  , according to Moore (1983: A66) and Squires (1984: 43).

oronlensis  ( Arca  ( Barbatia  ?) ) Gabb, 1881b: 346, pl. 44, fig. 21. Oronli Creek, Limon Prov., Costa Rica; so-called Miocene = Oligocene according to Dall 1898: 658). Type Material: “ Type ” ANSP 3482 ( Richards 1968: 71). Remarks: Arca oronlensis Gabb  , according to Dall (1898: 658).

ovalis  ( Arca  ?) Gabb , 1881a: 291–292, pl. 41, figs. 10–10a. [Junior homonym of Arca ovalis Nilsson, 1827  ]. Hacienda of Macanga, La Libertad Reg., Peru; Cretaceous. Type Material: Holotype UNMSM ( Rivera & Alleman 1974: 95). 

ovalis  ( Limopsis  ) Gabb, 1872d: 255, unfigured. Dominican Republic; Miocene. Type Material: Holotype ANSP 2657 ( Richards 1968: 71). Remarks: Pilsbry (1922: 402–403, fig. 35) figured the type.

ovalis  ( Meretrix  ) Gabb, 1864b: 166, pl. 30, fig. 251. Near Ft. Tejon, Kern Co., California; so-called Cretaceous (Division B) = Eocene ( Anderson & Hanna 1925: 159). Type Material: “Type” UCMP ( Merriam 1895); holotype UCMP 31453 ( Stewart 1930: 229). Remarks: Junior synonym of Cyclinella elevata (Gabb)  , according to Stewart (1930: 227–229).

ovalis  ( Yoldia  ) Gabb, 1872d: 255–256, unfigured. Dominican Republic; Miocene. Type Material: Holotype ANSP 3319 ( Woodring 1925: 23; Richards 1968: 71). Remarks: Pilsbry (1922: 402, fig. 34) figured the type, as did Woodring (1925, pl. 1, figs. 20–21). Yoldia (Orthoyoldia) ovalis Gabb  , according to Woodring (1925: 22–23).

ovata  ( Modiola  ) Gabb, 1860i: 396, pl. 68, fig. 31. [Junior homonym of Modiola ovata Calcara, 1841  ]. Yellow Limestone, Timber Creek, boundary between Gloucester and Camden counties, New Jersey ( Palmer & Brann 1965: 199); Paleocene [Eocene, Vincentown Formation ( Palmer & Brann 1965)]. Type Material: “ Type ” ANSP 18717 ( Richards 1968: 71). Remarks: Weller (1907: 508–509, pl. 55, fig. 17) figured the type specimen. Modiolus ovatus Gabb  , according to Palmer & Brann (1965: 199).

oviformis  ( Lithophagus  ) Gabb, 1864b: 185, pl. 25, fig. 168. Cow Creek, Shasta Co., California; Cretaceous (Division A) “Chico Group.” Type Material: Lectotype UCMP 11963 of Stewart (1930: 102). Remarks: Stewart (1927: 102) noted that there are two specimens in the UCMP collection, neither of which match the holotype as both have smaller beaks than the specimen figured by Gabb (1864: pl. 25, fig. 168). Stewart also stated “It can hardly be called a holotype so it is here designated the lectotype.” The larger specimen is most like Gabb’s figure and was likely the specimen noted by Merriam (1895).

pandaeformis ( Ostrea  ) Gabb, 1861b: 328, unfigured. Seven miles below Yazoo [City], Yazoo Co., Mississippi; socalled Cretaceous = Eocene ( Palmer & Brann 1965: 149–150). Type Material: Type material not located. Remarks: Junior synonym of Gigantostrea trigonalis (Conrad, in Wailes 1854)  , according to Palmer & Brann (1965: 149–150).

papyracea  (Lima) Gabb, 1881b: 348, pl. 45, fig. 26. Sapote, Limon Prov., Costa Rica; Miocene. Type Material: “ Type ” ANSP 3479 ( Richards 1968: 72).

papyracea  ( Pleuromya  ) Gabb, 1869b: 178–179, pl. 29, fig. 66. Cottonwood Creek, Shasta Co., California; Shasta Group?, Cretaceous. Type Material: Holotype ANSP 4390 ( Stewart 1930: 303, pl. 2, fig. 5; Richards 1968: 72). Remarks: Pleuromya  ? papyracea Gabb  , according to Stewart (1930: 303).

papyracea  ( Pleuronectia  ) Gabb, 1872d: 257, unfigured. Dominican Republic; Miocene. Type Material: “Type” ANSP 2863 ( Richards 1968: 72); holotype ANSP 2864 ( Waller 2011: 95). Remarks: Amusium papyracea (Gabb)  , according to Pilsbry (1922: 413, pl. 43, fig. 8) who also figured the type specimen. Amusium papyraceum  from the Miocene of the Dominican Republic is a true Amusium  on the basis of its muscle scar and auricular ribbing patterns ( Waller 1991: 38).

parallelus  ( Solen  ) Gabb, 1864b: 146–147, pl. 22, fig. 117. Bull's Head Pt., near Martinez, Contra Costa Co., California; so-called Cretaceous (Division B) = Eocene ( Moore 2003b: 4). Type Material: Lectotype ANSP 4481 of Stewart (1930: 291–292, pl. 7, fig. 1View FIGURE 1); Richards 1968: 72). Remarks: Solena (Plectosolen) parallelus (Gabb)  , according to Moore (2003b: 4).

parasitica  ( Exogyra  ) Gabb, 1864b: 205, pl. 26, figs. 192–192b, pl. 31, figs. 273–273a. Folsom, Amador Co., California; Cretaceous. Type Material: “Type lot” ANSP 4429 ( Richards 1968: 72; lectotype of Squires (2017: 40–43, figs. 131–132 [plastolectotype])). Remarks: Type figured by Gabb (1881a: 297–298, pl. 42, figs. 8–8a) and by Stewart (1930: 132, pl. 1, fig. 1View FIGURE 1). Gabb’s Exogyra parasitica  was identified by Coquand (1869) as Ostrea parasitica  , thus making Gabb’s name a secondary homonym of Ostrea parasitica Lindroth, 1788  . Coquand renamed Gabb’s species Ostrea washingtoni Coquand, 1869: 63–64  , pl. 33, figs. 5–9, but Gabb’s species does not belong in Ostrea  , thus making Coquand’s new name unnecessary. Amphidonte (Amphidonte) parasitica (Gabb)  , according to Elder (1991: E11, pl. 3, figs. 6, 10; pl. 4, figs. 17–23). Amphidonte parasitica (Gabb)  , according to Squires (2017: 40–43).

parilis  ( Corbula  ) Gabb, 1864b: 150, pl. 29, figs. 239–239a. Martinez, Contra Costa Co., California; so-called Cretaceous = Eocene ( Squires 1987: 71). Type Material: Lectotype ANSP 4466 of Stewart (1930: 288); Richards (1968: 73); holotype UCMP 33151, paratypes UCMP 12513–12515 (UCMP online database). Remarks: Lectotype figured by Stewart (1930: 288–289, pl. 3, fig. 5). Turner (1938: 65–66, pl. 8, fig. 13) figured a specimen taken to be the holotype in the UCMP collection after Stewart’s (1930) unnecessary lectotype designation. This specimen, UCMP 33151, fits Gabb’s original description in every detail. Hypotypes UCMP 33152–33154 of Turner (1938: 65). Weaver (1942 [1943]: 256, pl. 59, fig. 16) also figured the holotype. Corbula (Caryocorbula) parilis Gabb  , according to Squires (1987: 71).

parilis  ( Tellina  ) Gabb, 1864b: 160, pl. 30, fig. 243. [Junior homonym of Tellina parilis Deshayes, 1857  ]. Near Martinez, Contra Costa Co., California; Cretaceous. Type Material: Holotype and paratypes ANSP 4364 ( Stewart 1930: 203, pl. 1, fig. 11; Richards 1968: 73); syntypes (P. Callomon pers. comm. 2017). Remarks: “ Tellina  parilis Gabb  , according to Stewart (1930: 203).

parva  ( Anomia  ) Gabb, 1860b: 198, pl. 3, fig. 15. Chile; Cretaceous. Type Material: Type material not located. Remarks: Philippi (1887: 209, pl. 47, fig. 7) noted that this species was collected near Concepción, Concepción Prov., Chile. Riccardi (1988: 49) lists Anomia parva  from the Campanian and Maastrichtian of southern South America.

pauperculus ( Mytilus  ) Gabb, 1864b: 183, pl. 25, fig. 165. West of Martinez, Contra Costa Co., California; Cretaceous (Division A). Type Material: “Type” UCMP ( Merriam 1895); holotype UCMP 11962 ( Stewart 1930: 98); paratypes UCMP 12172, 12176, 32663 (UCMP online database). Remarks: Mytilus  ? pauperculus Gabb, according to Stewart (1930: 98). Stewart also noted that this is a very poorly preserved specimen and that it is “probably Cretaceous.”

peckhami  ( Pecten  ) Gabb, 1869a: 59–60, pl. 16, figs. 19–19a. Ojai Ranch, Santa Barbara Co. [Ventura Co.?], California (Gabb 1869a); Miocene; Contra Costa Co., California, Miocene according to Moore (1984: B15). Type Material: Lectotype MCZ 108523 [formerly MCZ 15405View Materials of Stewart (1930: 119–120, pl. 13, fig. 4)] (MCZ online database); “type” ANSP 4519 ( Richards 1968: 73). Remarks: Weaver (1942 [1943]: 96–97, pl. 21, fig. 4) reproduced Stewart’s figure. Delectopecten peckhami (Gabb)  of Arnold (1906), according to Moore (1984: B15, pl. 3, figs. 4, 5), who reported the lectotype lost. Palliolum (Delectopecten) peckhami (Gabb)  , according to the MCZ database, authority unknown.

pellucida  (Avicula) Gabb, 1864b: 186–187, pl. 25, fig. 172. Probably near Pacheco Pass, Santa Clara Co., California. Type Material: “Type” UCMP ( Merriam 1895); lectotype UCMP 11983 of H.E. Vokes (1939: 51, pl. 2, fig. 1View FIGURE 1). Remarks: Gabb (1864b) did not designate a holotype nor a type locality. Pteria pellucida (Gabb)  , according to H.E. Vokes (1939: 51), Moore (1983: A82, pl. 24, fig. 3), and Squires (2014b: fig. 4). This species was previously reported ambiguously as being both Cretaceous and Eocene in age but is actually restricted to the Late Cretaceous ( Squires 2014b: 221).

pennelli  ( Arca  ( Anadara  ) ) Gabb, 1872d: 254, unfigured. Dominican Republic; Miocene. Type Material: “ Type ” ANSP 2651 ( Richards 1968: 74). Remarks: Arca (Scaphara) pennelli Gabb  , according to Pilsbry (1922: 403, pl. 39, figs. 3–4).

penultimus ( Unio  ) Gabb, 1864b: 182–183, pl. 24, fig. 164. Peacock Coal Mine, Mt. Diablo District, Contra Costa Co., California; so-called Cretaceous (Division B) = Eocene ( Henderson 1935: 9). Type Material: “ Type ” UCMP ( Merriam 1895). Remarks: Hannibal (1912: 123) noted that the specimen is not a naiad but resembles Anomia  . Unio  ? penultimus, according to Henderson (1935: 94). perimbricata ( Plicatula  ) Gabb, 1869f: 16, pl. 6, fig. 15a. Volcano Mining District, Mineral Co., Nevada [about 30 mi. SE of Walker Lake]; Triassic or Jurassic. Type Material: Type material not located. Remarks: Squires & Saul (1997a: 287) reported that this species might belong to Harpax  . The material upon which this species is based represents "float" material derived from both Triassic and Jurassic rocks. This species is latest Triassic age, according to Squires & Saul (1997a: 287).

pertenue  ( Cardium  ( Laevicardium  )) Gabb, 1869g: 30–31, unfigured. [Junior homonym of Cardium pertenue Meek & Hayden, 1861  ]. Payta [= Paita], Piura Dept., Peru; Tertiary. Remarks: Figured in Gabb 1881a, pl. 35, figs. 9–9a. However, Laevicardium  is currently recognized as a full  genus (see Coan et al. 2000: 359).

pertenuis  ( Dosinia  ) Gabb, 1864b: 167–168, pl. 30, fig. 253. Jacksonville, Jackson Co., Oregon; Cretaceous. Type Material: Holotype ANSP 4426 ( Stewart 1930: 232, pl. 6, fig. 7; Richards 1968: 75). Remarks: “ Dosinia  pertenuis (Gabb)  , according to Stewart (1930: 232, 7).

pertenuis  ( Venus  ) Gabb, 1866: 22, pl. 5, fig. 37. Griswold's, on the road to New Idria, Monterey Co., California; Miocene. Type Material: “Type” UCMP ( Merriam 1895 [as Venus (Chione) pertenuis  ]); holotype UCMP 12000 ( Woodring 1927: 40–42, pl. 16, fig. 1View FIGURE 1; Stewart 1930: 220). Remarks: Gabb initially identified this species as Venus kennerlyi Carpenter in Reeve, 1863  , but followed with the statement "should it prove distinct, I propose the name of V. pertenuis  . " A more detailed description followed in 1869a: 55–56. Clementia (Egesta) pertenuis (Gabb)  , according to Woodring (1927: 40–42).

peruana  ( Anomia  ) Gabb, 1881a: 295–296, pl. 42, fig. 6. Quebrada del Alfarfar, south of Chachapoyas, Amazonas Reg., Peru; Cretaceous. Type Material: UNMSM (4 syntypes) ( Rivera & Alleman 1974).

peruana  ( Corbula  ) Gabb, 1881a: 283, pl. 40, fig. 11. Pariatambo coal mine, Cajamarca Reg., Peru; Cretaceous ( Rivera & Alleman 1974). Type Material: UNMSM (syntype) ( Rivera & Alleman 1974). Remarks: Corbula peruana  (?) Gabb, according to Willard (1966: 53).

peruana  ( Nucula  ) Gabb, 1881a: 292–293, pl. 41, fig. 1View FIGURE 1. Near Tingo (= Tinco), Ancash Reg., Peru; Liassic (= Jurassic). Type Material: Type material not located.

peruana  ( Tellina  ) Gabb, 1881a: 286, pl. 40, fig. 16. Pariatambo coal mine, Cajamarca Reg., Peru; so-called Jurassic = Cretaceous ( Rivera & Alleman 1974). Type Material: UNMSM (7 syntypes) ( Rivera & Alleman 1974).

peruana  ( Trigonarca  ) Gabb, 1881a: 291, pl. 41, figs. 9–9a. Near Ollon (= Oyón), Lima Reg., Peru; Cretaceous. Type Material: Type material not located.

pinnaforma ( Leda  ) Gabb, 1860g: 303, pl. 48, fig. 22 [not fig. 23, = Leda protexta  as per Ruhoff (1980: 434)]. Green marl, Burlington Co., New Jersey; Cretaceous. Type Material: “ Type ” ANSP 19519 ( Richards 1968: 76 [as Leda pinnaformis  ]). Remarks: Figured in Gabb (1860i: pl. 68, fig. 35). Whitfield (1885: 108–109, pl. 11, fig. 7 [same pagination and illustrations for Whitfield 1886]) figured the type specimen. Weller (1907: 373–374, pl. 29, fig. 27) reproduced Whitfield’s orginal figure. Nuculana pinnaformis (Gabb)  , according to Richards (1958c: 62, pl. 10, fig. 8), who also figured the type.

piochii  ( Inoceramus  ) Gabb, 1864b: 187–188, pl. 25, figs. 173–174 [in part, see "Remarks"]. North side of Mt. Diablo, Contra Costa Co., California; Cretaceous. Type Material: “Type” UCMP ( Merriam 1895 [as Aucella piochi  ]); “type lot” ANSP 4565 ( Richards 1968: 76 [as Aucella piochii  ]); holotype UCMP 11953 (UCMP online database). Remarks: Gabb (1869b: 194, pl. 32, figs. 92–92c) placed this species in Aucella  [now = Buchia  ]. Buchia piochii (Gabb)  , according to Stewart (1930: 108–112, pl. 2, fig. 3), who figured ANSP 4565. Figure 174 of Gabb = Mytilus quadratus Gabb  (1869b: 191, pl. 31, fig. 87), according to Stewart (1930: 97). Imlay (1959: 157– 159, pl. 17, fig. 10) figured a plastoholotype in the UCMP collection from Colusa Co., California. He also considered Gabb’s (1869b) specimens to be Aucella crassicollis Keyserling (1846)  . placerensis  ( Cardium  ( Protocardium  )) Gabb, 1864b: 173, pl. 24, fig. 156. Texas Flat, Placer Co., California; Cretaceous. Type Material: Holotype ANSP 4400 ( Richards 1968: 76 [as Protocardia placerensis  ]). Remarks: Protocardia placerensis (Gabb)  , according to Stewart (1930: 272–273, pl. 3, fig. 9), who figured the holotype.

plenus  ( Turnus  ) Gabb, 1864b: 146, pl. 22, fig. 116. North Fork of Cottonwood Creek, Butte Co., California; Cretaceous (Division A). Type Material: Lectotype UCMP 31459 of Stewart (1930: 296); paratypes UCMP 12223–12224 (UCMP online database) [= paralectotypes]; lectotype ANSP 4438 of Stewart (1930: 296–297, pl. 4, fig. 3, erroneously reported by Richards 1968: 76). Remarks: Richards (1968: 76) report of ANSP 4438 as being Stewart’s lectotype is erroneous as Stewart (1930: 296) clearly stated that a specimen of T. plenus  at UCMP “is probably the holotype but is here designated the lectotype since it is smaller that the original figure.”

polita  (? Mysia  ) Gabb, 1864b: 178. pl. 30, fig. 256. Martinez, Contra Costa Co., California; so-called Cretaceous (Division B) = Paleocene and Eocene ( Moore 1988: D26). Type Material: “Type” UCMP ( Merriam 1895); holotype  UCMP 11990View Materials ( Moore 1988: D26); paratypes  UCMP 12217View Materials, 32872View Materials ( UCMP online database). Remarks: Diplodonta (Diplodonta) polita (Gabb)  , according to Moore (1988: D26, pl. 8, fig. 8), who figured the holotype  .

ponderosa  (? Cardinia  ) Gabb, 1869f: 13, pl. 6, figs. 11–11a. New Pass , Desatoya Mountains , near Austin , Lander Co., Nevada; so-called Jurassic = Triassic Smith (1927: 111). Type Material: Holotype MCZ 110021View Materials ( MCZ online database). 

ponderosa  ( Homomya  ) Gabb, 1881a: 286, pl. 41, fig. 1View FIGURE 1. Elevated table lands near Cajamarca, Cajamarca Reg., Peru; Cretaceous. Type Material: Type material not located.

postradiata ( Lucina  ) Gabb, 1864b: 175–176, pl. 24, fig. 158 [not fig. 159, according to Gabb, 1869b: 189] Texas Flat, Placer Co., California; Cretaceous (Division A). Type Material: Type material missing ( Stewart 1930: 7).

primorsa (? Corbula  ) Gabb, 1864b: 148, pl. 22, figs. 120–120a. South side of Corral Hollow, Alameda Co., California; Cretaceous? Type Material: Type material missing ( Stewart 1930: 7).

protexta  ( Leda  ) Gabb, 1860g: 303, pl. 48, fig. 23 [not fig. 24, according to Gabb 1860i: 397]. Green marl, Burlington and Gloucester counties, New Jersey; Cretaceous. Type Material: Holotype ANSP 18729 ( Richards 1968: 78). Remarks: Nuculana protexta (Gabb)  , according to Gabb (1876b: 318). The holotype is an internal mold. Not Leda protexta Gabb, 1860  i.

protexta  ( Leda  ) Gabb, 1860i: 397, pl. 68, fig. 35. [Junior homonym of Leda protexta Gabb, 1860  g]. Lower Green marls, Freehold, Monmouth Co., New Jersey; Cretaceous. Type Material:?ANSP 18727. Remarks: Gabb (1860i: 397) thought Leda protexta Gabb, 1860  g and Leda protexta Gabb, 1860  i are the same species, but they are not. Leda protexta Gabb, 1860  i was renamed as Nuculana gabbiana Whitfield, 1885: 106–107  , pl. 11, figs. 11–13 [same pagination and illustrations for Whitfield 1886]. Weller (1907: 375–377, pl. 29, fig. 26) reproduced Whitfield’s type figure.

protexta  ? ( Leda  ) Gabb, 1864b: 199, pl. 26, fig. 185. Martinez area, Contra Costa Co., California; so-called Cretaceous = Paleocene to Oligocene? ( Moore 1983: A16). Type Material: Lectotype ANSP 4476a of Stewart (1930: 55–58, pl. 7, fig. 3). Remarks: Gabb (1864b) did not separate his earlier two forms of Leda protexta  from his 1864b species. Later, Gabb (1869b: 197–198) did separate them but used the name " Leda gabbii  " nomen nudum of Conrad for the 1864b species. Many workers (see Stewart 1930: 56) did likewise (i.e., referred to the 1864 species as Leda gabbii Conrad  after Gabb (1869b: 197). Because Gabb (1869b) gave locality information and some descriptive morphologic notes about this 1864b species, his use of Conrad's informal name became a formal name. The California species was reassigned to genus Nuculana  by Gabb (1876b: 318) and assigned to subgenus Saccella  by Moore (1983: A16); thus the current name is Nuculana (Saccella) gabbii (Gabb)  . pteropsis  ( Crassatella  ) Gabb, 1860i: 395, pl. 68, fig. 28. [Junior homonym of Crassatella pteropsis Conrad, 1860  ]. Hardeman Co., Tennessee; Ripley Group, also see Palmer & Brann (1965: 101); so-called Cretaceous = Paleocene, Kincaid Formation ( Palmer & Brann 1965: 101). Type Material: USNM 553 ( Richards 1958c: 186). Remarks: By page priority (see Wingard 1993), Gabb's species is a junior  primary homonym of Crassatella pteropsis Conrad, 1860: 279  , pl. 46, fig. 9. Gabb (1861e: 112) renamed his species as Crassatella cuneata  [see earlier listing in this present publication]. Also found in New Jersey, according to Whitfield (1885: 118–119 [same pagination for Whitfield 1886]) and Richards (1958c: 185–186).

pulchra  ( Noetia  ) Gabb, 1860i: 388, pl. 67, fig. 55. Eocene; and according to Palmer & Brann (1965: 248) = Stone City, Burleson Co., Texas; Eocene Claiborne Group. Type Material: “ Types ” ANSP 13261 ( Richards 1968: 78). Remarks: Pachecoa (Pachecoa) pulchra (Gabb)  , according to Stenzel et al. (1957: 65).

quadrata  ( Anatina  ) Gabb, 1869b: 177, pl. 29, fig. 64. North shore of Departure Bay, Nanaimo, Vancouver Id., Canada; Haslam Formation ( Usher 1952: 11), Cretaceous. Type Material: Holotype MCZ 108535 [formerly MCZ 15007View Materials ( Stewart 1930: 299)] (MCZ online database). Remarks: Periplomya  ? quadrata (Gabb)  , according to Stewart (1930: 299, pl. 6, fig. 13). He also noted that the only specimen available is an external impression of a right valve labeled “type” in Gabb’s handwriting and that it agrees fairly well with the dimensions original figure. Stewart’s figured specimen is a cast from the impression.

quadrata  ( Neaeromya  ) Gabb, 1872d: 247, pl. 10, figs. 4, 4a [mislabeled as 1a], 4b; 1872d: 247. Dominican Republic; Miocene. Type Material: “ Type ” ANSP 2787View Materials ( Richards 1968: 79)  . Remarks: Pilsbry (1922: 419–420, figs. 45a–e) figured the type.

quadrata  (? Tapes  ) Gabb, 1864b: 169, pl. 30, fig. 249. Near Ft. Tejon, Kern Co., California; so-called Cretaceous (Division B) = Paleocene?, Eocene? (doubtful from Ft. Tejon) ( Anderson & Hanna 1925: 162). Type Material: Lectotype ANSP 4464 of Stewart (1930: 234, pl. 7, fig. 9) ( Richards 1968: 79). Remarks: Pitar quadrata (Gabb)  , according to Stewart (1930: 234), who also noted that that his figured specimen was “the best in the Academy’s collection and if an undoubted holotype is not found, this specimen should be chosen as the lectotype.” Weaver (1942 [1943]: 180, pl. 104, fig. 2View FIGURE 2) reproduced Stewart’s figure.

quadrata  (? Tellina  ) Gabb, 1864b: 159, pl. 23, fig. 138. Tuscan Springs, Tehama Co., California; Cretaceous (Division A). Type Material: Academy of Natural Sciences of California [sic] (Gabb 1864b: 159); type material missing ( Stewart 1930: 7).

quadrata  ( Venilia  ) Gabb, 1861c: 364, unfigured. Upper Ripley Group, Mississippi; Cretaceous. Type Material: Type material not located. Remarks: Keen (1969: N650) corrected the spelling of the genus from Venilia  to Veniella  .

quadratus  ( Mytilus  ) Gabb, 1869b: 191, pl. 31, fig. 87. [Junior homonym of Mytilus quadratus Salter, 1848  ]. Martinez, Contra Costa Co., California; Cretaceous, “Chico Group.” Type Material: Lectotype ANSP 4397 of Stewart (1930: 97–98, pl. 1, fig. 9) ( Richards 1968: 79). Remarks: Mytilus  ? quadratus Gabb  , according to Stewart (1930: 97). As mentioned earlier in this paper, Inoceramus piochii Gabb, 1864b  (pl. 25, fig. 174, not fig. 173) is Mytilus quadratus Gabb, 1869b  .

quindecemradiata  ( Arca  ) Gabb, 1860a: 95, pl. 2, fig. 2View FIGURE 2. "Common in the more northerly portions of the Cretaceous deposits of New Jersey;" so-called Cretaceous = Eocene Vincentown Formation ( Palmer & Brann 1965: 54). Type Material: “ Type ” ANSP 18797 ( Richards 1968: 79).

radiata  ( Meekia  ) Gabb, 1864b: 192, pl. 25, fig. 179a. Rancho de San Luis Gonzaga, in Pacheco's Pass, Santa Clara Co., California; Cretaceous (Division A). Type Material: “Type” UCMP ( Merriam 1895); lectotype UCMP 10313 of Saul & Popenoe (1962: 298, pl. 3, fig. 3); paralectotypes UCMP 10314, 14780, 34658, 34767–34770, 34839 (UCMP online database).

raimondii  ( Arca  ( Scapharca  )) Gabb, 1869g: 31, unfigured. Payta [= Paita], Piura Dept., Peru; Tertiary. Type Material: Holotype UNMSM ( Rivera & Alleman 1974). Remarks: Figured in Gabb (1881a: pl. 35, figs. 10–10a). Scapharca  is now considered a full  genus (see Newell 1969: N256).

raimondii  ( Barbatia  ?) Gabb, 1881a: 290, pl. 41, fig. 6. Pariatambo coal mine, Cajamarca Reg., Peru; Cretaceous ( Rivera & Alleman 1974: 100). Type Material: Holotype UNMSM ( Rivera & Alleman 1974: 100). Remarks: Parallelodon raimondii (Gabb)  , according to Rivera & Alleman (1974: 100).

raimondii  ( Corbula  ) Gabb, 1881a: 284, pl. 40, fig. 12. Pariatamba coal mine, Cajamarca Reg., Peru; age not given. Type Material: Type material not located.

raimondii  ( Pecten  ) Gabb, 1881a: 293, pl. 42, figs. 1–1aView FIGURE 1. Hill of Potosi, on the road from Lima to Jauja, Junín Reg., Peru; age not given. Type Material: Type material not located.

raimondii  ( Pholadomya  ) Gabb , 1881a: 284–285, pl. 40, fig. 15. Between Combayoa and Polloc, Cajamarca Reg., Peru; Jurassic? or probably Cretaceous. Type Material: Holotype UNMSM ( Rivera & Alleman 1974: 100). 

reevei  ( Crassatella  ) Gabb, 1872d: 252, unfigured. Dominican Republic; Miocene. Type Material: ANSP 2687 ( Pilsbry 1922: 415). Remarks: Gabb (1872: 252) compared the conchological features of a single valve with the living Crassatella antillarum Reeve, 1842  and stated “if however, these differences should prove to be constant, the fossil form might be separated under the name of C. Reevei.” Brown & Pilsbry (1912: 515), Pilsbry (1922: 415), and Olsson (1922: 212) all recognized the differences as valid and accepted the new species as Crassatellites reevei (Gabb)  .

remondi  (? Panopaea  ) Gabb, 1864a: 28, pl. 5, fig. 23. San Marcial, Sonora, Mexico; Triassic. Type Material: Type material not located. Remarks: Panopea remondi (Meek)  [sic], according to Dumble (1900: 137).

remondianum  ( Cardium  ) Gabb, 1864b: 172, pl. 23, fig. 153. Near Benicia, Solano Co., California; Cretaceous (Division A). Type Material: Holotype? ANSP 4394 ( Richards 1968: 80). Remarks: Pachycardium  ? remondianum (Gabb)  , according to Stewart (1930: 278, pl. 3, fig. 8), who noted that “the figured specimen, though somewhat smaller than the size mark of the original figure, is probably the holotype [ANSP 4394] and is at least the lectotype.” Pachycardium remondianum (Gabb)  , according to Nielsen (1993: 84).

remondii  ( Tellina  ) Gabb, 1864b: 156, pl. 22, fig. 132. Cochran's, six miles east of Mt. Diablo, Contra Costa Co., California; so-called Cretaceous = Paleocene and Eocene ( Moore 2003b: 18). Type Material: Holotype UCMP 31451 ( Stewart 1930: 200–201, pl. 8, fig. 1View FIGURE 1). Remarks: Holotype refigured by Gabb (1869b: 182, pl. 29, fig. 71). Tellina  (subgenus?) remondii Gabb  , according to Moore (2003b: 18, pl. 4, fig. 4).

rhysomia ( Venus  ) Gabb, 1861d: 369–370, unfigured. Santa Barbara, Santa Barbara Co., California; Miocene?, Pleistocene? Type Material: Unknown ( Keen & Bentson 1944: 121). Remarks: Probably a synonym of Transenella tantilla (Gould, 1853)  , according to Keen & Bentson (1944: 121). Likely a senior synonym of Nutricola lordi (Baird, 1863)  , according to Coan et al. (2000: 383).

richthofeni  ( Lucina  (Here )) Gabb, 1866: 29, pl. 8, figs. 49a–b. San Fernando Valley, north of Los Angeles, Los Angeles Co., California; Pliocene, Pico Formation? ( Stewart 1930: 182). Type Material: “Type” UCMP ( Merriam 1895); lectotype ANSP 4492 of Stewart (1930: 182, pl. 15, fig. 3) and paratype [= paralectotype] ANSP 4492a of Stewart (1930: 182, pl. 17, fig. 5) ( Richards 1968: 81). Remarks: Considered a junior  synonym of Here excavata (Carpenter, 1857), according to Stewart (1930: 181), as well as by Coan et al. (2000: 263). Moore (1988: D13, pl. 3, figs. 11–13) figured the lectotype.

ripleyana  ( Venus  ) Gabb, 1860i: 393–394, pl. 68, fig. 22. Hardeman Co., Tennessee; Ripley Group, so-called Cretaceous = Paleocene ( Palmer & Brann 1965: 273. Type Material: Holotype ANSP ( Palmer & Brann 1965:

273). Remarks: Pitar  ? ripleyanus (Gabb), according to Palmer & Brann (1965: 273).? Pitaria ripleyana (Gabb)  , according to Toulmin (1977: 593).

ripleyanus ( Lithophagus  ) Gabb, 1861b: 326–327, unfigured. Crosswicks, Burlington Co., New Jersey; Cretaceous. Type Material: Type ANSP 19580 ( Richards 1958c: 157). Remarks: Lithophaga ripleyana (Gabb)  , according to Gabb (1876b: 311), Wade (1926: 70), and Richards (1958c: 156–157).

rotundata  (Axinaea) Gabb, 1860i: 396, pl. 68, fig. 33. Ripley Group, Eufala [= Eufaula], Barbour Co., Alabama; Cretaceous. Type Material: “ Type ” ANSP 16414 ( Richards 1968: 81). Remarks: Glycymeris rotundata (Gabb)  , according to Stephenson (1955: 108).

sabulosum  ( Cardium  ( Granocardium  )) Gabb, 1869d: 267, pl. 36, fig. 14. Sierra de las Conchas, near Arivechi, Sonora, Mexico; Cretaceous. Type Material: “Type” ANSP 4771 ( Richards 1968: 82 [as Granocardium subulosum  on p. 88]). Remarks: Scott (1978: 898–899, pl. 2, figs. 6–9) figured the holotype [ANSP 4771]. Perrilliat (1989: 311, fig. 118c) reproduced Gabb's figure. Granocardium (Granocardium) sabulosum (Gabb)  , according to Allmazan-Vazquez (1990).

saffordi  ( Arca  ) Gabb, 1860i: 397, pl. 68, fig. 38 [mislabeled as fig. 37]. Hardeman Co., Tennessee; so-called Cretaceous = Paleocene ( Palmer & Brann 1965: 121). Type Material: Lost ( Palmer & Brann 1965: 121). Remarks: Cucullaea saffordi (Gabb)  , according to Palmer & Brann (1965: 121).

saffordi  ( Modiola  ) Gabb, 1860i: 395–396, pl. 68, fig. 30. Ripley Group, Hardeman Co., Tennessee; so-called Cretaceous = Paleocene ( Palmer & Brann 1965: 54). Type Material: Lost ( Palmer & Brann 1965: 54). Remarks: Cf. Brachidontes saffordi (Gabb)  , according to Palmer & Brann (1965: 54).

sagittata  ( Axinea  ( Limopsis  ?)) Gabb, 1864b: 197–198, pl. 31, figs. 267–267a. Near Ft. Tejon, Kern Co., California; Eocene. Type Material: Holotype ANSP 4422 ( Richards 1968: 82). Remarks: Glycymeris (Glycymerita) sagittata  , according to Givens (1974: 42–43) and Moore (1983: A54, pl. 12, fig. 17), who figured the holotype [referred to as lectotype in text and plate caption].

sapotensis ( Meretrix  ) Gabb, 1881b: 343, pl. 44, fig. 15. Sapote, Limon Prov., Costa Rica; Miocene. Type Material: “ Type ” ANSP 3489 ( Richards 1968: 82).

scapha ( Pandora  ) Gabb, 1866: 18–19, pl. 4, fig. 32. West of Martinez, Contra Costa Co., California; Miocene. Type Material: “Type” ANSP 4539 ( Richards 1968: 83). Remarks: Stewart (1930: 304, pl. 16, fig. 3) figured the holotype.

sella  ( Meekia  ) Gabb, 1864b: 191–192, pl. 25, fig. 179. Near Martinez, Contra Costa Co., California; Cretaceous (Division A). Type Material: Holotype UCMP 31457 ( Stewart 1930: 305; Saul & Popenoe 1962: 301, pl. 1, fig. 6); “types” ANSP ( Richards 1968: 83).

semilaevis ( Tellina  ) Gabb, 1860f: 567, unfigured. Chiriqui, Panama; Miocene. Type Material: “ Type ” ANSP 3947 ( Richards 1968: 83).

shastaensis (Lima) Gabb, 1869b: 201, pl. 33, fig. 100. Cottonwood Creek, Shasta Co., California; Shasta Group, Cretaceous. Type Material: Holotype ANSP 4434 ( Richards 1968: 84). Remarks: Holotype figured by Stewart (1930: 124, pl. 5, fig. 13). Emended by Anderson (1938: 111) as shastensis.

siskiyouensis  ( Modiola  ) Gabb, 1864b: 184, pl. 30, fig. 260. Summit of Siskiyou Mountains, Jackson and Klamath counties, Oregon; Cretaceous. Type Material: Holotype ANSP 4399 ( Stewart 1930: 99, pl. 6, fig. 10; Richards 1968: 84). Remarks: Volsella siskiyouensis (Gabb)  , according to Stewart (1930: 99). slackiana ( Leda  ) Gabb, 1860i: 397, pl. 68, fig. 36. Dark Marl, Crosswicks, Burlington Co., New Jersey; Cretaceous. Type Material: “Type” ANSP 18796 ( Richards 1968: 84). Incorrectly cited as ANSP 19876 by Richards (1958c: 60) but correct in plate 10 caption. Remarks: Whitfield (1885: 103–104, pl. 11, fig. 2View FIGURE 2 [same pagination and illustrations for Whitfield 1886]) illustrated the type. Richards (1958c: 60, pl. 10, figs. 3, 6) also figured the type and correctly noted the type number as ANSP 18796. Junior synonym of Nuculana percrassa (Conrad, 1858)  , according to Wingard & Sohl (1988: D14).

solitaria  ( Nucula  ) Gabb, 1869b: 197, pl. 32, fig. 94. Texas Flat, Colusa Co., California; Cretaceous. Type Material: Type material missing ( Stewart 1930: 7). Remarks: Whiteaves (1895: 122–123) provisionally compared this species to his species Nucula hornbyensis  from Hornby Id., British Columbia, Canada. He noted that his species may only be a variety of N. solitaria  but also argued that if Gabb’s species is correct “it must have a very different marginal outline” and “his illustration represents a much more triangular shell than that of N. Hornbyensis [sic], with a more prominent beak, and more ponted at both ends.”

sonorensis ( Pholadomya  ) Gabb, 1869d: 265, pl. 36, fig. 12. Sierra de las Conchas, near Arivechi, Sonora, Mexico; Cretaceous. Type Material: Whereabouts unknown according to Perrilliat (1989: 353, fig.132l) who reproduced Gabb's figure.

soror  ( Janira  ) Gabb, 1872d: 257, unfigured. Dominican Republic; Miocene. Type Material: ANSP 2862 ( Pilsbry 1922: 410, pl. 44, figs. 1–2View FIGURE 1View FIGURE 2). Remarks: Pecten soror (Gabb)  , according to Pilsbry (1922: 410). Euvola soror (Gabb)  , according to Waller (2011: 105–108).

spillmani  ( Pecten  ) Gabb, 1860i: 402, pl. 68, fig. 3. Alabama; Eocene = Yazoo Formation ( Dockery 1980: 156). Type Material: Holotype? ANSP ( Richards 1968: 85). Remarks: Chlamys spillmani (Gabb)  , according to Tucker- Rowland (1938: 29). See Dockery, (1980: 156) for age control.

spiralis ( Myophoria  ) Gabb, 1881a: 289–300, pl. 41, figs. 4–4a. Pariatambo coal mine, Cajamarca Reg., Peru; socalled Liassic = Cretaceous ( Rivera & Alleman 1974). Type Material: UNMSM (2 syntypes) ( Rivera & Alleman 1974).

squarrosa ( Ctenoides  ) Gabb, 1861c: 366, unfigured. White limestone, Alabama; Cretaceous. Type Material: “ Type ” ANSP ( Richards 1968: 85). Remarks: Lima squarrosa (Gabb), according to Rindsberg (2000).

staleyi  ( Dosinia  ) Gabb, 1866: 24–25, pl. 7, fig. 42. Mark West Creek branch of Russian River, Sonoma Co., California; Pliocene. Type Material: Neotype ANSP 4490 of Stewart (1930: 222–223, pl. 15, fig. 4) ( Richards 1968: 85). Remarks: Venerupis (Protothaca) staleyi (Gabb)  , according to Stewart (1930: 222–223). Weaver (1942 [1943]: 170–171, pl. 104, fig. 3) reproduced Stewart’s figure. Protothaca staleyi (Gabb)  , according to Peck (1960: Table 2).

stella  ( Posidonomya  ) Gabb, 1864a: 32, pl. 6, fig. 31. Star Canyon, Humboldt Mining Region, Humboldt Co., Nevada; Triassic. Type Material: Holotype? “Type lot” ANSP 30789 ( Richards 1968: 86). Remarks: Posidonia stella (Gabb)  , according to Smith (1927: 113, pl. 104, fig. 10) who reproduced Gabb’s original figure.

subaequalis ( Siliqua  ) Gabb, 1872d: 247, unfigured. Dominican Republic; Miocene. Type Material: “ Type ” ANSP 2677View Materials ( Richards 1968: 86)  . Remarks: Pilsbry (1922: 426, text-fig. 48) figured the type.

subaustralis  (Axinaea) Gabb, 1861c: 365, unfigured. New Jersey; Cretaceous. Type Material: Type material not located. Remarks: Weller (1907: 414–415) reported Gabb’s species to be Pectunculus subaustralis d’Orbigny, 1850  , but Pectunculus  is a subjective synonym of Glycymeris da Costa, 1778  ( Newell 1969: N567).

subcircularis  ( Lucina  ) Gabb, 1864b: 176, pl. 24, fig. 160. [Junior homonym of Lucina subcircularis Deshayes, 1857  ]. Texas Flat, Placer Co., California; Cretaceous (Division A). Type Material: Holotype ANSP 4401 ( Richards 1968: 86). Remarks: Gabb's homonym renamed as Myrtea  ? gabbi Stewart, 1930: 188  . pl. 5, fig. 2View FIGURE 2. subcircularis  ( Monotis  ) Gabb, 1864a: 31, pl. 6, figs. 29–29a. Gifford's Ranch, Plumas Co., California; Triassic. Type Material: “Type lot?” ANSP 30795 ( Richards 1968: 86). Remarks: Pseudomonotis subcircularis (Gabb)  , according to Smith (1927: 120, pl. 104, fig. 6), who reproduced one of Gabb’s original figures. According to Grant- Mackie & Silberling (1990: 247), Gabb's species is the type species of subgenus Pacimonotis Grant-Mackie & Silberling, 1990  .

subcompressa ( Corbula  ) Gabb, 1860i: 394, pl. 68, fig. 24. Two miles east of Middleton, Hardeman Co., Tennessee; so-called Cretaceous = Paleocene ( Palmer & Brann 1965: 96). Type Material: ANSP? ( Johnson 1905: 17; Palmer & Brann 1965: 96).

subquadrata  ( Cardita  ) Gabb, 1860g: 303, pl. 48, fig. 21 [not figs. 22a, b]. [Junior honomyn of Cardita subquadrata Conrad, 1847  ]. Green marl, Burlington Co., New Jersey; Cretaceous [Eocene? ( Richards 1968)]. Type Material: “ Type ” ANSP 19373 ( Richards 1968: 87). Remarks: Gabb’s homonym renamed as Venericardia perantiqua Conrad, 1865  , which Whitfield (1885: 232–233 [same pagination for Whitfield 1886]) referred to as Cardita perantiqua (Conrad)  .

subquadrata  ( Mysia  ) Gabb, 1872d: 252, unfigured. [Junior homonym of Mysia subquadrata Conrad, 1856  ). Dominican Republic; Miocene. Type Material: “ Type ” ANSP 2675 ( Richards 1968: 193 [as Mysia subquadrata  ]). Remarks: Dall (1900: 1183) renamed Gabb’s species Diplodonta gabbi  .

sulcata ( Chione  ) Gabb, 1860f: 567, unfigured. Chiriqui, Panama; Miocene. Type Material: “ Type ” ANSP 3946 ( Richards 1968: 88). Remarks: Junior synonym of Chione (Lirophora) mactropsis Conrad, 1855  according to Dall (1903: 1294–1295). Lirophora (Panchione) mactropsis (Gabb)  , according to Woodring (1982: 704–707).

sulcicosta  ( Arca  ) Gabb, 1866: 31, pl. 9, figs. 53–53a. [Junior homonym of Arca sulcicosta Nyst, 1836  ]. Mark West Creek, Sonoma Co., California; Pliocene. Type Material: “Type” UCMP ( Merriam 1895); holotype UCMP 32488, paratype? UCMP 32489 ( Keen & Bentson 1944: 29). Remarks: Gabb's homonym renamed Arca schizotoma Dall, 1898  , which Keen & Bentson (1944: 29) synonymized with Arca trilineata Conrad, 1857  [= Anadara trilineata (Conrad, 1857)  ].

tayloriana  ( Ostrea  ) Gabb, 1866: 34, pl. 12, figs. 60–60a. [Junior homonym of Ostrea tayloriana King, 1848  ]. San Marcos Pass, near Santa Barbara, Santa Barbara Co., California; so-called Miocene = Eocene and Oligocene ( Moore 1987: C33, pl. 29, figs. 7–8). Type Material: “Type” UCMP ( Merriam 1895); holotype UCMP 12005 ( Moore 1987: C33). Remarks: Striostrea  ? tayloriana (Gabb)  , according to Moore (1987: C33). Nomen dubium, according to Squires (2018: 15).

tecticosta  ( Ostrea  ) Gabb, 1860i: 403, pl. 68, figs. 47–48. New Jersey; so-called Cretaceous = Cretaceous to Paleocene ( Palmer & Brann 1965: 240). Type Material: Syntypes ANSP 18761 (from New Jersey) and 18808 (from Tennessee) ( Richards 1958c: 107–108; Richards 1968: 88). Remarks: Junior synonym of O. pusilla Nilsson, 1827  , according to Gabb (1876b: 321) but not confirmed by subsequent workers (e.g., Stephenson 1955: 111; Palmer & Brann 1965: 240). Whitfield (1885: 33–34, pl. 3, figs. 2View FIGURE 2 –3 [same pagination and illustrations for Whitfield 1886]) also figured type 18761. Richards (1958c: 107–108, pl. 16, figs. 13, 14) figured type 18761. Cubitostrea tecticosta (Gabb)  , according to Rindsberg (2000).

tenua  ( Pachydon  ) Gabb, 1869e: 199–200, pl. 16, figs. 6–6a. Pebas, on Ambiyacu River [= Ampiyacu River], two miles above confluence with Marañon River [= Amazon River], Loreto Prov., Peru; Pebas Formation, so-called Pliocene? = Miocene ( Wesselingh 2006: 241). Type Material: “ Type ” ANSP 20061 ( Richards 1968: 89 [as Pachydon tenuis  ]). Remarks: Anisothyris tenuis (Gabb)  , according to Willard (1966: 68). Pachydon tenuis Gabb  , according to Wesselingh (2006: 241). See remarks under the genus Pachydon  (herein).

tenuis  ( Cyprinella  ) Gabb, 1864b: 170–171, pl. 23, figs. 151–151a. Contra Costa Co., California; Cretaceous [probably Tertiary according to Stewart 1930: 198]. Type Material: “Type” UCMP ( Merriam 1895 [as Cyprinella (Diodus) tenuis  ]); cotype UCMP 11959 (UCMP online database); lectotype ANSP 4448 of Stewart (1930: 198, pl. 16, fig. 2View FIGURE 2). Remarks: Diodus tenuis (Gabb)  , according to Gabb (1869b: 242) and Stewart (1930: 198). Stewart also noted “inasmuch as this species is the type of the genus Diodus  , which was proposed for this hinge, this specimen (ANSP 4448) is taken for the lectotype of Diodus tenuis  ” (see Stewart 1930: pl. 16, fig. 2View FIGURE 2).

tenuisculpta  ( Nucula  ) Gabb, 1872d: 255, unfigured. Dominican Republic; Miocene. Type Material: “ Type ” ANSP 2656 ( Richards 1968: 89). Remarks: Pilsbry (1922: 401–402, pl. 38, fig. 6) figured the type. Nucula (Nucula) tenuisculpta Gabb  , according to Woodring (1973: 488–489).

tenuissima (? Mactra  ) Gabb, 1869b: 179–180, pl. 29, fig. 68. Martinez, Contra Costa Co., California; Cretaceous =?Cretaceous or?Paleocene ( Moore 2003a: 21). Type Material: Holotype ANSP 4361 ( Richards 1968: 89). Remarks: Holotype figured by Stewart (1930: 213, pl. 1, fig. 3). Mactromeris  ? ( Mactromeris  ?) tenuissima (Gabb), according to Moore (2003a: 21).

tenuitesta ( Pecten  ) Gabb, 1861b: 327–328, unfigured. Burlington Co., New Jersey; Cretaceous. Type Material: “ Type ” ANSP 18759 ( Richards 1968: 89). Remarks: Pecten tenuitestus Gabb  , according to Richards (1958c: 126– 127, pl. 23, fig. 8) who also figured the type. Junior synonym of Pecten quinquenarius Conrad, 1853  , according to Wade (1926: 65–66).

tetrahedra ( Venus  ) Gabb, 1864b: 163, pl. 30, fig. 247. Near Martinez, Contra Costa Co., California; Cretaceous (Division A). Type Material: Lectotype ANSP 4379 of Stewart (1930: 219, pl. 1, fig. 10) ( Richards 1968: 89). Remarks: “ Venus  ” tetrahedra Gabb, according to Stewart (1930: 219).

texana  ( Corbula  ) Gabb, 1860i: 387, pl. 67, fig. 54. Texas; Eocene [Stone City beds, Claiborne Group ( Palmer & Brann 1965: 207)]. Type Material: “Type lot” ANSP 13262 ( Richards 1968: 89) [= unfigured syntypes]; figured syntype lost, according to Palmer & Brann (1965: 207). Remarks: Notocorbula texana (Gabb)  , according to Palmer & Brann (1965: 207).

texana  ( Perna  ) Gabb, 1861d: 371, unfigured. Caddo Peak, Johnson Co., Texas; so-called Eocene = Cretaceous, Woodbine Group ( Palmer & Brann 1965: 261). Type Material: “Type” ANSP 3959 ( Richards 1968: 89). Remarks: “ Perna  texana Gabb  , according to Palmer & Brann (1965: 261, pl. 1, fig. 7), who figured ANSP 3959 and referred to it as the holotype. Modiolus (Brachydontus) texanus Gabb  , according to Dall (1898: 796).

texanus  ( Pecten  ) Gabb, 1861c: 365, unfigured. [Junior homonym of Pecten texanus Roemer, 1852  ]. Texas, New Jersey?; Cretaceous. Type Material: USNM ( Shattuck 1903: 17) [not in online database]. Remarks: Whether or not Pecten texanus Gabb, 1861c  is conspecific with Neithea texana (Roemer, 1852)  needs clarification, but will be difficult to accomplish because Gabb did not figure his species. Shattuck (1903: 17, pl. 5, figs. 6–8) treated them as synonyms, but Stanton (1947: 45–46, pl. 38, figs. 2View FIGURE 2, 4, 5; pl. 39, figs. 3–5, 7) and Akers & Akers (2002: 145, fig. 117 [in part], 434) did not follow Shattuck’s conclusion.

texta  (? Gari  ) Gabb, 1864b: 155, pl. 22, fig. 130. Near Martinez, Contra Costa Co., California; so-called Cretaceous (Division B) = Eocene ( Squires 1987: 68). Type Material: Holotype ANSP 4471 ( Richards 1968: 89). Remarks: Gari texta Gabb  , according to H.E. Vokes (1939: 93). Holotype figured by Stewart (1930: 283, pl. 7, fig. 12).

thirsae  ( Gryphaea  ) Gabb, 1861b: 329–330, unfigured. “Nanafalia” [Bluff, Tombigbee River, Marengo Co.], Alabama; so-called Cretaceous = Eocene Nanafalia Formation ( Palmer & Brann 1965: 225). Type Material: Lectotype USNM 494957 ["570"] of Gabb (1861b) as noted by Palmer & Brann (1965: 225–226) who also noted that “the specimen apparently is the one measured by Gabb and would be the obligatory lectotype.” Remarks: Ostrea thirsae (Gabb)  , according to Gardner (1945: 76–77, pl. 5, figs. 16, 18) who figured the lectotype as did Heilprin in White 1884: 311, pl. 63, figs. 4–6. Odontogryphaea thirsae (Gabb)  , according to Palmer & Brann (1965: 225) and Glawe et al. (2011: 977–985). torta  ( Cyprimeria  ) Gabb, 1876b: 308–309, unfigured. Georgetown, Quitman Co., Georgia; Cretaceous. Type Material: “Type” ANSP 20163 ( Richards 1968: 90). Remarks: Questionably a junior  synonym of Cyprimeria alta ( Conrad, 1875)  , according to Stephenson (1941: 212), confirmed by Stephenson (1955: 120–121).

torta  ( Plicatula  ) Gabb, 1881a: 295, pl. 42, fig. 5. Quebrada of Colpamayo, near Chota, Cajamarca Reg., Peru; Cretaceous. Type Material: Type material not located.

translucida  (Crenella ( Modiolaria  )) Gabb, 1881c: 377, pl. 47, fig. 81. Between Limon and Moen (= Moin), Limon Prov., Costa Rica; so-called Pliocene = Pliocene/Pleistocene Moín Formation ( Robinson 1993: 252). Type Material: Holotype ANSP 3449 ( Richards 1968: 90). Remarks: Junior synonym of Musculus lateralis (Say, 1822)  , according to Weisbord (1964: 100).

translucida  ( Leda  ) Gabb, 1864b: 199–200, pl. 30, fig. 269. Cow Creek, Shasta Co., California; Cretaceous. Type Material: Holotype and paratype ANSP 4395 ( Richards 1968: 90) are actually syntypes (P. Callomon, pers. comm. 2017). Remarks: Lembulus  (?) translucida (Gabb)  , according to Stewart (1930: 59, pl. 6, fig. 11), who figured the holotype.

translucidum ( Cardium  ( Protocardium  )) Gabb, 1869b: 187, pl. 30, figs. 82–82a. Martinez, Contra Costa Co., California; Cretaceous. Type Material: Holotype, missing ( Richards 1968: 90). Remarks: Protocardia translucida (Gabb)  , according to Stewart (1930: 273, pl. 3, fig. 4), who figured the holotype.

transversa  ( Crassatella  ) Gabb, 1861c: 364–365, unfigured. New Jersey; Cretaceous. Type Material: Holotype ANSP 18744 ( Richards 1958c: 185, pl. 29, fig. 8; 1968: 90). Remarks: Crassatellites transversus  according to Richards (1958c: 185). According to Wingard (1993: 60), this species is based on a specifically indeterminable internal mold, and the name should be restricted to just the type specimen.

transversa  ( Cucullaea  ) Gabb, 1861b: 326, unfigured. [Junior homonym of Cucullaea transversa Rogers & Rogers, 1839  ]. Arneytown, Burlington Co., New Jersey; Cretaceous. Type Material: Holotype ANSP 18222 ( Richards 1968: 90). Remarks: Gabb's primary homonym renamed Cucullaea gabbi  by Johnson (1905).

transversa  ( Limopsis  ) Gabb, 1864b: 200, pl. 26, fig. 186. Texas Flat, Placer Co., California; Cretaceous. Type Material: As the original specimen was described from the California Academy of Sciences, it may have been destroyed in the fire following the 1906 San Francisco earthquake ( Stewart 1930: 87). He also designated UCMP 31445 as a neotype. Remarks: “ Limopsis  transversa  according to Allan (1935: 24) and he noted that it “is of an altogether different shape from Limopsis  .” Stewart (1930: 88) suggested that it may be in the genus Barbatia  . Not a Limopsis  , according to Squires (2012: 12).

traskii  ( Corbula  ) Gabb, 1864b: 149, pl. 22, figs. 121–121a. Texas Flat , Placer Co., California; Cretaceous (Division A). Type Material: Lectotype UCMP 155538View Materials of Squires & Saul (2004b: 112, fig. 13). Remarks: Carycorbula traskii (Gabb)  , according to Squires & Saul (2004b: 112). 

traskii  ( Pecten  ) Gabb, 1864b: 200–201, pl. 26, figs. 187–187a. Texas Flat, Placer Co., California; Cretaceous (Division A). Type Material: The original specimen was described from the California Academy of Sciences and was likely destroyed in the fire that followed the 1906 San Francisco earthquake ( Stewart 1930: 121); “type” ANSP 4404 ( Richards 1968: 91). Remarks: According to Stewart (1930: 121–122), ANSP has the fragment of ANSP 4404 figured by Gabb (1869b: 198, pl. 32, fig. 95) but it is from the Cretaceous of Vancouver Id., Canada. He also suggested that a neotype be designated from material from Texas Flat, California. Lyriochlamys traskii (Gabb)  , according to Elder (1991: E10).

trigona  ( Venilia  ) Gabb, 1861b: 324–325, unfigured. Boonton, Morris Co., New Jersey; Cretaceous. Type Material: “ Type ” ANSP 18787 ( Richards 1968: 91 [as Veniella trigona