Pagurus smithi ( Benedict, 1892 )

Lemaitre, Rafael, 2023, The taxonomic status of Pagurus bouvieri (Faxon, 1895), an obscure name, and redescription of Pagurus smithi (Benedict, 1892), a poorly known species (Decapoda: Paguridae), Nauplius (e 2023011) 31, pp. 1-19 : 13-17

Pagurus smithi ( Benedict, 1892)

( Figs. 4C, D , 5 , 6 )

Eupagurus smithi Benedict, 1892: 4 (type locality: USFC Albatross, sta 2823, Gulf of California, eastern Pacific) .

Pagurus smithi — Glassell, 1937: 259 (new combination). — Haig et al., 1970: 19. — Hendrickx, 1993: 283, 309 (list). — Hendrickx and Harvey, 1999: 372.

Not Eupagurus Smithii A. Milne-Edwards and Bouvier, 1893: 140 , pl. 10, figs 1–12 (preoccupied name) [= Pagurus bouvieri ( Faxon, 1895) = P. politus ( Smith, 1882) ].

Type material. Lectotype, herein selected: male 7.9 mm, northeastern Pacific , south part of Gulf of California, Mexico, USFC Albatross, sta 2823, 24°18’00”N 110°22’00”W, 48.5 m, 30 April 1888 ( USNM 16716 ) . Paralectotypes: Northeastern Pacific , USFC Albatross : 4 males 6.1–7.6 mm, same station data as lectotype ( USNM 108258 ) ; 6 males 3.0–6.0 mm, 4 females 3.3–5.1 mm, 1 ovig female 3.9 mm, sta 3014, Gulf of California , S of Tiburón Island, Sonora, Mexico, 28°28’00”N 112°04’30”W, 53 m, 23 March 1889 ( USNM 16717 ) ; 1 male 6.0 mm, Gulf of California , N of Punta Estrella, Baja California, Mexico, sta 3030, 31°07’00”N 114°29’00”W, 37 m, 27 March 1889 ( USNM 16718 ) ; 3 males 4.5–8.2 mm, 1 female 5.5 mm, Gulf of California , Baja California, Mexico, sta 3031, N of Punta Estrella, 31°06’45”N 114°28’15”W, 60 m, 27 Mar 1889 ( USNM 16719 ) ; 4 females 3.1–4.3mm, Baja California, Santa Margarita Island , Mexico, sta 3038, 24°30’N 111°53’00”W, 57 m, 8 April 1889 ( USNM 16720 ) ; 1 male 7.5 mm, Baja California, Magdalena Bay , Mexico, sta 3042, 24°38’00”N 112°05’30”W, 31 m, 9 April 1889 ( USNM 16721 ) .

Non type material. Northeastern Pacific : 1 female 3.0 mm, Cerros Island , Baja California, Mexico, [28°12’N 115°15’W], haul 1631, 32.9 m, 9 January 1908, coll. Marine Biological Association of San Diego ( USNM 1293191 ) ; 2 females 3.0, 6.4 mm, Santa Maria Bay , off Hughes Point, Baja California, Mexico, [24°46’01”N 112°16’59”W], 55–73 m, 7 Mar 1934 ( USNM 1021120 ) ; 5 males 5.1–7.5 mm, 1 ovig female 6.0 mm, Santa Maria Bay , Baja California, Mexico, 27°24’22”N 112°17’52”W, 18–37 m, 20 January 1938, coll. S.A. Glassell ( USNM 1293197 ) .

Redescription. Shield ( Fig. 5A ) slightly broader than long; anterolateral margins sloping; with distinct slit parallel to each anterior dorsolateral margin;anterior margin between rostrum and lateral projections concave; posterior margin truncate;dorsal surface smooth, nearly naked except for short tufts of setae, with short linea-d on each side. Rostrum obtusely triangular, without terminal spine, slightly bulging dorsally; lateral projections triangular, with small terminal spine; branchiostegites and posterior carapace membranous except for weakly calcified postero-median plate, glabrous except for finely setose anterior margins of branchiostegites.

Ocular peduncles ( Fig. 5A ) stout, approximately 0.7 times (including cornea) as long as shield, slightly constricted medially, glabrous; corneas dilated. Ocular acicles subtriangular, with sub-marginal spine, separated basally by approximately half basal width of 1 acicle, dorsal surface of distal portion concave.

Antennular peduncle ( Fig.5A ) slender, exceeding distal margin of ocular peduncle (including cornea) by approximately 0.2 times length of ultimate segment. Ultimate and penultimate segments glabrous. Basal segment ( Fig. 5B ) lateral face with subrectangular distal lobe; proximal lobe bearing fringe of long bristle-like setae and terminating in strong spine.

Antennal peduncle ( Fig. 5A ) exceeding distal margin of ocular peduncle (including cornea) by approximately 0.5 times length of fifth segment. Fifth segment unarmed or with scattered setae. Fourth segment unarmed. Third segment with small ventrodistal spine. Second segment with dorsolateral distal angle strongly produced forming strong spine (reaching to approximately 0.75 times length of fourth segment) with finely denticulate mesial margin; dorsomesial distal angle with small sharp spine, with short setae on mesial surface. First segment with small spine on laterodistal margin. Antennal acicle reaching to approximately distal margin of cornea, curving outwardly, terminating in acute spine,mesial margin with tufts of setae. Flagellum reaching to approximately mid-length of right chela, naked.

Chelipeds ( Fig. 2C, D ) distinctly unequal, right longer and broader, general shape subovate. Right chela somewhat dorsoventrally f lattened, with dorsal surfaces densely covered with honeycomb pattern of flat-topped mushroom-like tubercles each with small spine ( Fig.5C ) almost entirely covering surface beneath; ventral surfaces with numerous small, low tubercles; dactyl and fixed finger of each chela with strongly curved corneous tips crossed when closed.

Right chela ( Fig. 2D ) with dactyl approximately1.4 times as long as palm (measured along mesial margin), nearly glabrous; dactyl with mesial margin armed with row of strong spines, cutting edge consisting of irregular-sized calcareous teeth and row of tufts of setae on dorsomesial and ventromesial margins. Fixed finger with armature similar to dactyl. Palm dorsal surface convex, lateral margin well delimited by row of strong arrowhead-like spines increasing in size distally and continuing on fixed finger; dorsomesial margin rounded, mesial surface armature similar to dorsal surface. Carpus with dorsal, lateral and mesial surfaces sparsely setose, covered with numerous spines, dorsolateral margin with row of strong spines; dorsodistal margin spinulose. Merus subtriangular in cross section; lateral and mesial faces fairly smooth; with ventrolateral and ventromesial margins having well-spaced small low tubercles. Ischium with small low tubercles on ventral surface. Coxa with small blunt spines on ventrodistal margin, and row of setae on ventromesial margin.

Left cheliped ( Fig. 2C ) general shape subovate, somewhat dorsoventrally flattened. Chela dorsal surface armed on dorsal and ventral surfaces similarly to right chela, nearly glabrous except for tufts on mesial surface of dactyl and fine setae on mesial margin of palm. Dactyl and fixed finger each with strongly curved corneous tips crossed when closed; lateral surface of dactyl with numerous tufts of setae; dactyl approximately 1.4 times as long as palm (measured on mesial margin), cutting edge with row of fused corneous teeth and tufts of setae;cutting edge of fixed finger with more or less similarly sized calcareous teeth and tufts of short setae. Palm with dorsolateral margin usually somewhat expanded laterally and well delimited by row of strong arrowhead-like spines decreasing in size distally and continued on fixed finger. Carpus with dorsal, lateral and mesial surfaces sparsely setose, covered with numerous spines; dorsomesial margin with row of strong spines; dorsodistal margin spinulose; ventral surface with small low tubercles. Merus subtriangular in crosssection; lateral and mesial faces fairly smooth; with ventrolateral and ventromesial margins having well-spaced small low tubercles. Ischium with small low tubercles on ventral surface. Coxa with small blunt spines on ventrodistal margin, and row of setae on ventromesial margin. Ischium unarmed, with moderated long setae on mesial surface.

Pereopods 2 and 3 ( Fig. 6A–D ) similar from left to right. Dactyl broadly curved, approximately 1.8–1.9 times as long as propodus (measured along dorsal margin), dorsal margin armed with small spines proximally, terminating in sharp corneous claw; lateral and mesial surfaces with median longitudinal crease extending distally from base to about 0.75times length of dactyl; with dorsodistal and ventromesial row of setae on distal half, ventromesial margin with row of typically 10–15 slender corneous spinules interspersed with shorter corneous spinules on distal half, and tufts of setae on proximal half. Propodus with dorsal and dorsolateral margins sparsely setose, armed with small spines (more numerous and stronger on pereopod 2), otherwise glabrous, smooth. Carpus sparsely setose dorsally, dorsal margin armed with row of strong spines increasing in size distally, dorsolateral surface with small spines or low tubercles; laterodistal margin spinulose on pereopod 2, unarmed in pereopod 3; otherwise glabrous, smooth. Merus with scattered short setae on dorsal and ventral margins; lateral and mesial surfaces glabrous, smooth; dorsodistal and laterodistal margin spinulose (pereopod 2), or unarmed (pereopod 3); ventrodistal margin with minutes spines or tubercles.Sternite XI (pereopods 3; Fig. 5D ) with anterior lobe semicircular, distally setose.

Pereopod 4 ( Fig. 6E ) semichelate. Dactyl curved, sub-triangular, terminating in sharp corneous claw,with ventrolateral row of minute, fused corneous teeth; with dorsal tufts of long setae.Propodus with dorsodistal tuft of long setae;propodal rasp well developed, consisting of 3–5 rows of ovate corneous scales.Carpus with long setae dorsodistally, otherwise glabrous.

Merus and ischium with setae on ventral margins.

Pereopod 5 chelate. Dactyl with rasp of small scales on lateral surface.Propodal rasp occupying nearly half of lateral face of propodus. Carpus, merus, ischium and coxa sparsely setose. Sternite XIII (pereopod 5; Fig. 5E ) subdivided anteriorly into 2 setose lobes (densely setose in ovigerous females).

Pleon with distinct membranous, f leshy protuberance anteroventrally (more developed towards left side). Uropods strongly asymmetrical, left largest.Telson ( Fig.5F ) weakly asymmetrical, with distinct deep transverse suture separating anterior and posterior lobes; anterior lobes with long setae on lateral margins; posterior lobes separated by narrow median cleft, terminal margins forming 2 subtriangular projections armed with strong corneous-tipped spines, each projection terminating in distinctly stronger simple or double spine.

Male with paired gonopores, each masked by forwardly directed setae; with unpaired left pleopods 3–5. Females with paired gonopores; unpaired left pleopods 2–5 (only pleopods 2–4 carrying eggs when ovigerous).

Distribution. Northeastern Pacific, so far only from the Gulf of California and the west coast of Baja California. Depth: 18 to 73 m.

Habitat. Inhabits gastropod shells frequently heavily encrusted with barnacles and anthozoans.

Remarks. Benedict’s (1892) description of this species did not include illustrations or a list of material he examined. Neither did Benedict give an indication of which specimen was to be designated as the holotype. Benedict specimens came from the collections obtained on USFC Albatross, and thus those must be considered as the syntype series from which a lectotype is herein selected.Since the original description, this species has been reported only by Glassell (1937), Haig et al. (1970), Hendrickx (1993), and Hendrickx and Harvey (1999).

Figures

Figure 2. Carpus and chela of chelipeds, dorsal view. Pagurus politus (Smith, 1882), male lectotype 7.9 mm, USFC Albatross, sta 2823, northwestern Atlantic, Martha’s Vineyard, Massachusetts (USNM 16716): A, left; B, right. Pagurus smithi (Benedict, 1892), male lectotype 7.9 mm, USFC Albatross, sta 2823, northeastern Pacific, southernpart of Gulf of California, Mexico (USNM 16716): C, left; D, right. Scales = 1 mm.

Figure 4. Paratypes of Eupagurus smithii A. Milne-Edwards and Bouvier, 1893 (preoccupied name, = Eupagurus bouvieri Faxon, 1895): A, B, ovigerous females 6.6 mm (A, dorsal view; B, ventral view); C, ovigerous female 7.7 mm (dorsal view), “Bache” Expedition, Gulf of Mexico, Sand Key, Florida (MCZ 4005). Photos: D.L. Felder.

Figure 5. Pagurus smithi (Benedict, 1892), lectotype male7.9 mm, northeasternPacific,southern Gulf of California, Mexico, USFC Albatross,sta 2823 (USNM 16716): A, shield and cephalic appendages, dorsal view; B, right basal antennular segment, dorsal view; C, portion of dorsolateral surface of right chela near base of fixed finger and lateral margin of chela, dorsolateral view; D, anterior and posterior lobes of sternite XI (between third pereopods), ventral view; E, sternite XIII (between fifth pereopods), ventralview; F, telson, dorsal view. Scales = 2 mm (A), 1 mm (B, C–F).

Figure 6. Pagurus smithi (Benedict, 1892), lectotype male7.9 mm, northeasternPacific,southern Gulf of California, Mexico, USFC Albatross, sta 2823 (USNM 16716): A, right second pereopod, lateral view; B, dactyl of same, mesial view; C, right third pereopod, lateral view; D, dactyl of same, mesial view; E, propodus and dactyl of left fourth pereopods, lateral view. Scales = 3 mm (A, C), 2 mm (B, D), and 1 mm (E).