Galeodinopsis semperi ( Wiechmann, 1871 )

Garilli, Vittorio & Parrinello, Daniela, 2014, Taxonomy and palaeobiogeography of the Cenozoic Euro-Mediterranean rissoid gastropod Galeodinopsis and its relationship with close genera, Acta Palaeontologica Polonica 59 (2), pp. 379-406 : 393-396

Galeodinopsis semperi ( Wiechmann, 1871)

Figs. 12 , 13.

1845 Rissoa Duboisii nov. sp.; Nyst 1845: 418, n° 358, pl. 37: 19.

1864 Rissoa multicostata nov. sp.; Speyer 1864: 290, pl. 41: 3–5, non R. multicostata Adams, 1850 nec R. multicostata Garrett, 1857 , which belong to Rissoina d’Orbigny, 1840 .

1871 Alvania Semperi nov. sp.; Schwartz v. Mohrenstern (in litt.) Wiechmann 1871: 58–60.

1954 Alvania duboisi (Nyst) ; Glibert and Heinzelin 1954: 351, pl. 5: 13. 1964 Alvania (Arsenia?) multicostata ( Speyer, 1864) var.?; Tembrock 1964: pl. 7: 6, 7.

2008 Alvania (Alvania) multicostata (Speyer) ; Müller 2008: pl. 4: 10a, b. 2011 Alvania (Alvania) multicostata ( Speyer, 1864) ; Müller 2011: pl. 5: 18a, b, 19a, b, 20, 21, 23a, b, and 24a, b.

Type material: Repository of Wiechmann (1871) types unknown.

Type locality: Wiechmann (1871: 58–59) based his species on shells from Söllingen (type locality of Rissoa multicostata Speyer, 1864 ) and also cited conspecific specimens from Crefeld (also known as Krefeld), Doberg and Sternberg. All these localities, which are Chattian in age, are in N Germany.

Type horizon: Oligocene marine sand, as for Söllingen (see Anderson 1960: 24).

Material studied.—The type specimen ( Fig. 12 )of Rissoa duboisii Nyst, 1845 in IRSNB, 3956, Tg2b layer of Klein-Spauwen, Belgium, Tongrian; 3 shells in MNHU, MB.Ga.7745, as Rissoa multicostata Speyer, Magdeburg ?, Sachsen-Anhalt, Germany, Middle Oligocene; 1 shell in MNHU, MB.Ga.43, illustrated by Tembrock (1964: pl. 7: 6) as Alvania (Arsenia?) multicostata (Speyer, 1964) var.?, from Latdorfian bed, Latdorf, Germany; 1 shell in BGR, X1239, illustrated by Tembrock (1964: pl. 7: 7) as Alvania (Arsenia?) multicostata (Speyer, 1964) var.?, drill hole Drehna 5/1960, Lusatia/ Brandenburg, Germany, Late Oligocene; 1 incomplete shell in BGR, X9909, illustrated by Gründel (1997: fig. 2) as Alvania (Arsenia) semperi Wiechmann, 1871 .

Description.—Shell small, conical-turrited, reaching about 4.1 mm in height and 2.6 mm in width (about 2.55 X 1.6 in type specimen of Rissoa duboisii ); Ht/W variable, mainly depending on occurrence and position of varices on last whorl, from 1.4 to about 1.7. Protoconch multispiral, conical, with 2.3 to 2.7 rounded whorls and rather immersed nucleus. Protoconch 1 of about 0.7 whorls with netted sculpture consisting of at least 6 very thin spiral lirae and numerous, irregular, short, very narrow axial segments occurring in interspaces between lirae. Intersection of spiral and axial forming rough hexagons or squares. Protoconch 2 sculptured with very few microscopic dots roughly forming one or two discontinuous fine spiral threads in suprasutural position. Protoconch/teleoconch boundary marked by weakly sinuous, very thin lip. Teleoconch with up to at least 3.5 convex whorls. Whorls sculptured with equal axial and spiral elements forming clathrate pattern of acute nodules at their intersections.Axial ribs slightly curved, opisthocline to almost straight; 18–24 on penultimate whorl; lacking on shell base. Main spiral sculpture of cords overriding axial ribs. Cords 3–4 on early teleoconch and on penultimate whorl; 7–10 and 3–7 (depending on shell height) on last whorl and shell base, respectively. A further, much weaker, almost flat subsutural cord occurs on

→ Fig. 11. Rissoid gastropod Galeodinopsis germanica sp. nov., abandoned mine-pit Höllkopf, Glimmerode, south of Hessisch-Lichtenau, Hessen, Germany, Chattian (Late Oligocene) Kasseler Meeressand. A. Holotype SMF 335576, in apertural (A 1), dorsal (A 2), and profile (A 3) views. B. Paratype SMF 336790, in apertural view. C. Paratype SMF 336789, in apertural (C 1) and dorsal (C 2) views; protoconch in dorsal view (C 3), white arrows indicate approximate position of the protoconch/teleoconch boundary; details of protoconch showing sculpture on late protoconch 2 (C 4), protoconch 1 and early protoconch 2 (C 5). D. Paratype SMF 336788, in apertural view (D 1), teleoconch sculpture (D 2), details of microsculpture showing the typical Manzonia -like pitted pattern (D 3, D 4), and the Alvinia -like pattern (white arrows) on the obsolete subsutural cord (D 5). E. Paratype SMF 336787, in apertural view. Scale bars: A

1

–A

3

, D

1

, E, 1 mm; B, C, 300 μm; C

3

, D

2

, 100 μm; C

4

, C

5

, 30 μm; D

3

, D

5

, 20 μm; D

4

, 10 μm. Fig. 13. Rissoid gastropod Galeodinopsis semperi ( Wiechmann, 1871) from the Paleogene of Germany. A. Juvenile specimen BGR X1239, same speci- → men as illustrated by Tembrock (1964: pl. 7: 7) as Alvania (Arsenia?) multicostata ( Speyer, 1864) var.?, from drill hole Drehna 5/1960, Lusatia/ Brandenburg, Oligocene, Chattian, in apertural view (A 1); protoconch in profile view (A 2), white arrows indicate the protoconch/teleoconch boundary; detail of protoconch 1 showing trace of the netted sculpture (A 3); detail of teleoconch sculpture (A 4); teleoconch microsculpture showing the almost flat subsutural cord (A

5

). B. Specimen MNHU MB.Ga.7745.1 with delicate sculpture from Magdeburg?, Sachsen-Anhalt, Oligocene, Rupelian, in apertural (B

1

), dorsal

B 2), and profile (B 3) views; teleoconch microsculpture on spiral cord (B 4). C. Specimen MNHU MB.Ga.43, from Latdorf, Latdorfian, same specimen classified by Tembrock (1964: pl. 7: 6) as Alvania (Arsenia?) multicostata ( Speyer, 1864) var.?, in apertural (C 1) and dorsal (C 2) views. D. Specimen MNHU MB.Ga.7745.2 from Magdeburg?, Sachsen-Anhalt, Oligocene, Rupelian, in apertural view, strongly resembling Rissoa multicostata Speyer, 1864 from the original illustration (pl. 41: 3). Scale bars: B

1

–B

3

, C, D, 1 mm; A

1

, 200 μm; A

2

, 100 μm; A

3

–A

5

, B

4

, 20 μm.

GARILLI AND PARRINELLO—RISSOID GASTROPOD GALEODINOPSIS 395

A 1 B1 B 2 B3 A 2 A 4 B4 A 5 A 3 C1 C2 D

some specimens. Teleoconch microsculpture on spiral cords of fine, raised, closely spaced spiral threads simulating a sort of pseudopitted pattern on a few specimens. Threads more raised on subsutural cord, where they do not show any trace of pitted microsculpture. Last whorl well expanded to strongly inflated, making up about 0.7 total shell height; some shells with one varix at angles of 90° to about 200°.Aperture wide, ovate, very rounded anteriorly, with acute angle posteriorly, making up about 0.5 and about 0.6–0.7 of total shell and of last whorl height, respectively. Outer lip weakly sinuous to almost straight, double-rimmed due to a thin rim on its edge; internally smooth; externally with very marked varicose swelling covered by spiral cords. Inner lip weakly curved, with very thin expansion in columellar area, forming very narrow to obsolete umbilical chink.

Remarks.— Nyst (1845) described this species under the name Rissoa duboisii while renaming Cyclostoma scalare Dubois, 1831 , preoccupied by Rissoa scalaris Michaud, 1831 . However C. scalare Dubois, 1831 is a different species attributed to Manzonia (Fig. 3A; see also Kowalke and Harzhauser 2004). Therefore, the Nyst’s (1845) name should not be used, in accordance with the provisions of ICZN art. 72.7, and the available name for the species discussed here is Alvania semperi Wiechmann, 1871 , being Rissoa multicostata Speyer, 1864 a primary junior homonym.

The tentative placement in Arsenia Monterosato, 1884 Tembrock 1964, as A. multicostata ) is incorrect.As we have shown ( Fig. 7C–E ), Turbo punctura Montagu, 1803 , the type species of Arsenia, is quite distant, having a different shell shape, a single-rimmed aperture and a protoconch 1 with no netted sculpture; even its microsculpture is totally different, being almost smooth. T. punctura is regarded as falling within Alvania sensu stricto, following Ponder (1985). Therefore, the attribution to Alvania Risso, 1826 , as indicated by Müller 2008, 2011), also is rejected. The microsculpture of Galeodinopsis semperi is comparable to that of rissoid species such as Turbo zetlandicus Montagu, 1815 ( Fig. 5A 2 ), type of Flemellia, and is very similar to that observed in G. biangulata compare Figs. 12I , 13A 4, A 5 with 9B 2), although only a few specimens of G. semperi show a trace of the narrow axial bridges that form the typical pitted surface in Manzonia or in the type species of Galeodinopsis . Galeodinopsis semperi can be separated from G. biangulata by the occurrence of at least 3 cords (vs. 2) starting from the first teleoconch whorl. Another main difference is in the number of axial ribs: 18–24 in G. semperi , 13–16 in most specimens of G. biangulata . Also, the spiral cords on the penultimate and last whorls of G. semperi are more numerous. As in G. biangulata , G. semperi is characterized by a turrited-shouldered teleoconch similar to that of Alvinia . The quite inflated last whorl, bearing varices on many specimens, is the main character allowing this species to be placed within Galeodinopsis .

Galeodinopsis semperi is quite variable, above all in teleoconch sculpture, which is strongly to gently clathrate. Morphs with marked sculpture (as in the type specimen of Rissoa duboisii in Nyst coll., Fig. 12A–D, H , and in a Latdorfian shell, Fig. 13C) bear fewer cords (18 on the penultimate whorl), whereas other morphs with more delicate sculpture (Fig. 13B, D), matching the original illustration of Rissoa multicostata Speyer (1864 : pl. 41: 3–5), have more spiral cords (up to 24 in the material studied) and axial ribs (4 vs. 3 in the type specimen of R. duboisii ). All these morphs show the same pattern of teleoconch microsculpture (compare Figs. 12I and 13B 4) and are regarded as intraspecific variability of one species. Wiechmann (1871, ex litteram from Schwartz 1864) described Alvania semperi as a slender form comparable to “ Alvania multicostata Speyer ” with which it shares the same reticulate sculptural pattern. This form is characterized by finer sculpture, with more numerous ribs, and by a proportionally less inflated last whorl. Koenen (1867) reported a similar form at Söllingen together with typical shells of R. multicostata Speyer, 1864 . This form, possibly the same as illustrated by Müller (2011: pl. 5: 24a, b), is regarded as the expression of the wide intraspecific variability of G. semperi . Koenen (1867) and Wiechmann (1871) also noted the sculptural variability of Speyer’s (1864) species, when describing a morph comparable with Rissoa partschi Hörnes, 1856 , a species of Alvinia having a simple peristome (see Kowalke and Harzhauser 2004: fig. 8b). This morph, characterized by more prominent sculpture, is represented by the material described by Nyst (1845) as R. Duboisii .

The name “ Rissoa Semperi Schwartz v. Mohrenstern” used by Görges (1957) with reference to Schwartz (1864, “Rissoiden, 2”) is not valid, as also stated by Anderson (1960). In fact, Schwartz (1864) never described or quoted this species/name in his Die Familien der Rissoiden.

The specimen illustrated by Janssen (1978a: pl. 11: 30) as Alvania (Arsenia) semperi Wiechmann is very close to Alvania rupeliensis Tembrock, 1964 (pl. 7: 8). However we were not able to get shells of this last species, particularly the holotype that should be housed at BGR, and indicate wheth- er it is a well-established taxon or simply a synonymous of Galeodinopsis semperi . The worn shell illustrated by Janssen (1978a, pl. 11: 32) might belong to G. semperi .

Stratigraphic and geographic range. —Late Eocene/very Early Oligocene at Latdorf (Latdorfian Stage) and Magderburg ( Tembrock 1964; Müeller 2011, as Alvania multicostata ), central Germany, and Klein-Spauwen, Belgium (Tongrian Stage); Early Oligocene (Rupelian) of Belgium (Late Tongrian Stage), at Klein-Spauwen, and north-central Germany, at Magderburg; Late Oligocene (Chattian) at Doberg and Crefeld, north-western Germany ( Wiechmann 1871), and Söllingen ( Speyer 1864; Wiechmann 1871), north-central Germany.

Figures

Fig. 12. A–I. Rissoid gastropod Galeodinopsis semperi (Wiechmann, 1871), the type specimen IRSNB 3956 (Nyst coll.) of synonymous Rissoa duboisii Nyst, 1845, Tg2b layer of Klein-Spauwen, Belgium, Late Tongrian. Specimen in apertural (A), profile (B), and dorsal (C) views; early teleoconch whorls (D); protoconch in profile view (E), black arrows indicate the protoconch/teleoconch boundary; subapertural view (F); detail of protoconch 1 showing trace of the netted sculpture (G); detail of teleoconch sculpture (H); microsculpture on spiral cord (I). J. Original label in Nyst’s handwriting with the citation of “type” and references to the original description and illustration in Nyst, 1845. Scale bars: A–C, 1 mm; D 200 μm; E, F, H, 100 μm; G, 50 μm; I, 30 μm.

Fig. 7. Rissoid gastropods Alvania areolifera (Sandberger, 1863) (A, B) and Alvania punctura (Montagu, 1803), type species of Arsenia Monterosato, 1891 (C–E). A. Specimen MNHU MB.Ga.7749.1, Waldböckelheim, Rheinland-Pfalz, W Germany, Rupelian, Oligocene, in apertural view. B. Specimen MNHU MB.Ga.7749.2, same site as in A, in dorsal view. C. Slender specimen ex VG, MZB 49971, Recent, station CS’96/54, 135 m deep, Graham Bank, Strait of Sicily, in dorsal view (C 1), protoconch (C 2), sculpture of protoconch 1 (C 3), detail of teleoconch microsculpture (C 4). D. Specimen ex VG, MZPD Mal 2044a, Sicilian, Early Pleistocene, Acqua dei Corsari, Ficarazzi, Palermo, NW Sicily, in apertural view. E. Specimen ex VG, MZPD Mal 2044b, with inflated last whorl, same site as in D, in dorsal view. Scale bars: A, B, C , D, 1 mm; E, 500 μm; C , 100 μm; C , C , 25 μm.

Fig. 5. Teleoconch microsculpture in the type species of rissoid gastropods Alvinia Monterosato, 1884 and Flemellia Nordsieck, 1972. A. Alvinia zetlandica Montagu, 1815), type species of Flemellia, ex MF, MZPD Mal 2046a (same specimen as in Fig. 4C), Calabrian, Early Pleistocene of Lazzaro, Vallone Catrica, Reggio Calabria, S Italy, showing closely spaced spiral threads on shell surface at different magnifications. B. Alvinia weinkauffi (Weinkauff, 1868 ex Schwartz von Mohrenstern ms), type species of Alvinia, ex VG, MZPD Mal 2048 (same specimen as in Fig. 4B), Recent, infralittoral bottom (37 m deep) off Formica Island, W Sicily, showing narrow spiral threads on shell surface at different magnifications. Scale bars: A , B , 50 μm; A , B , 10 μm.

Fig. 2. Rissoid gastropod Galeodinopsis tiberiana (Coppi, 1876), type species of Galeodinopsis Sacco, 1895 from Rio Grizzaga sands, Gagliardella, Fogliano, Maranello, Modena, N Italy, type locality, Piacenzian, Pliocene. A. Specimen ex MF, MZPD Mal 2035a, in apertural view. B. Specimen ex MF, MZPD Mal 2035b, in dorsal view. C. Specimen ex MF, MZPD Mal 2035c showing typical Manzonia-like teleoconch microsculpture (C 1) and detail of protoconch 1 with netted sculpture (C 2). Black arrows indicate the protoconch 1/protoconch 2 boundary. Scale bars: A, B, 1 mm; C, 20 μm.