Testacellidae

Salvador, Rodrigo Brincalepe, 2013, The fossil pulmonate snails of Sandelzhausen (Early / Middle Miocene, Germany): Succineidae, Testacelloidea and Helicoidea, Zootaxa 3721 (2), pp. 157-171 : 161-163

Family Testacellidae

Genus Testacella Draparnaud

Testacella zellii Klein, 1853 ( Fig. 5 )

Testacella zellii Klein, 1853: 204 (pl. 5, fig. 1). Testacella larteti larteti [sic]: Gall, 1972: 7.

Testacella zelli [sic]: Schlickum, 1976: 15 (pl. 3, fig. 51). Testacella sp.: Moser et al., 2009b: 48.

Material examined. BSPG 1959 II 17689 (1 spcm.).

Stratigraphic occurrence. The single specimen has no stratigraphical data, but Moser et al. (2009b) indicate either layer B or C1.

Description. Shell small, ear-shaped, vestigial. Apex starkly pointed. Shell smooth, except for growth lines. Aperture large and elongated, with a near right angle on the encounter between parietal and palatal regions; parietal and columellar region greatly thickened.

Measurements (in mm). ¾ whorl; H = 1.7; D = 2.3.

Previous identification of the material. Gall (1972: Nr. 3): Testacella larteti larteti [sic] Dupuy. Moser et al. (2009b: Nr. 42): Testacella sp.

Discussion. The shell is vestigial in this monotypic family and, therefore, is of very limited taxonomical value. The single specimen found in Sandelzhausen is fragmentary; nevertheless it presents some distinctive features. As already stated by Moser et al. (2009b), the present specimen differs from T. lartetii Dupuy by being much deeper and by having an almost right angle on its aperture and thus cannot be classified as this species. These features, alongside the starkly pointed apex, compare fittingly to T. zellii , a species known only from a few fossil sites of the German Early/Middle Miocene Silvana-beds (Silvanaschichten; Schlickum, 1976).

Recent Testacella species are voracious predators, preying on slugs, snails, centipedes and, especially, earthworms; living mainly underground and requiring, at least, a moderately moist soil cover (Barker & Efford, 2004). This burrowing habit should make it difficult for the shells to be carried away post-mortem and preserved in the lake sediments, hence its rarity in Sandelzhausen.

Superfamily Helicoidea

Family Elonidae

Genus Klikia Pilsbry

Klikia cf. c oarctata (Klein, 1853) ( Figs. 6–9 )

Helix c oarctata Klein, 1853: 206 (pl. 5, fig. 6).

Klikia (Apula) coarctata coarctata: Wenz, 1923a: 534 .

Klikia (Klikia) giengensis giengensis: Gall, 1972: 10 .

Klikia (Apula) coarctata: Schlickum, 1976: 17 (pl. 4, fig. 60); Kókay, 2006: 92. Soosia (Prosoosia) cf. godarti: Moser et al., 2009b: 49 (fig. 6B).

Material examined. BSPG 1959 II 16144 (1 spcm.), 17301 (1 spcm.).

Stratigraphic occurrence. Layers C3 (probably) and D1. Specimen BSPG 1959 II – 16144 comes from a sand lens in the western part of the fossil site, which is probably layer C3 according to Moser et al. (2009b).

Description. Shell small, depressed; shell height ~1/2 its width. Protoconch (~1 whorl) blunt, wide, apparently smooth; transition to teleoconch unclear. Teleoconch sculptured by regularly distributed fine papillae, giving the impression of axial striae; papillae apparently stronger closer to suture and to umbilicus. Whorls’ profile slightly convex. Suture well-marked, deep. Whorls regularly increasing in size, but with a decrease in size in the last quarter of body whorl. Body whorl with conspicuous constriction right before the aperture (“extralabial depression” sensu Binder, 2008). Aperture crescent-shaped; aperture height ~4/5 its width; aperture width ~2/5 shell width. Peristome greatly reflected.

Measurements (in mm). BSPG 1959 II 16144 ( Figs.6–9 ): 4¾ whorls; H = 5.0; D = 9.3; h = 3.3; d = 4.0.

Previous identification of the material. Gall (1972: Nr. 18): Klikia (Klikia) giengensis giengensis (Klein) . Moser et al. (2009b: Nr. 54, fig. 6B): Soosia (Prosoosia) cf. godarti Michaud sensu Sandberger.

Discussion. The specimens from Sandelzhausen compares fittingly with K. coarctata , a species from the Silvanaschichten of southwestern Germany (MN5–6; Klein 1853; Schlickum 1976). However, one of the main features of this species, a covered umbilicus (Klein 1853; Harzhauser & Binder 2004), cannot be seen in the material from Sandelzhausen, since the single complete shell preserved shows a collapsed umbilical region. In any case, the degree in which the umbilicus is covered seems to be variable in some Klikia species (Harzhauser & Binder 2004) and as such, it might not be such a useful diagnostic character.

Family Helicidae

Genus Cepaea Held

Cepaea cf. eversa Deshayes, 1851 ( Figs. 10–13 )

Helix eversa Deshayes, 1851: 395 (pl. 1, figs. 5–7). Cepaea eversa eversa: Wenz, 1923a: 617 .

Hemicycla asperula cf. leymerieana: Gall, 1972: 10. Cepaea eversa larteti (in part): Gall, 1972: 10; Gall, 1973: 10 (pl.1, figs. 4–6). Cepaea silvana silvana (in part): Gall, 1972: 11.

Cepaea eversa: Hír & Kókay, 2004: 89 .

“ Cepaea ” sp. 1. (in part): Moser et al., 2009b: 50. “ Cepaea ” sp. 2.: Moser et al., 2009b: 50.

Material examined. BSPG 1959 II 460 (1 spcm.), 461 (1 spcm.), 16157 (1 spcm.), 16158 (1 spcm.), 16160 (1 spcm.), 16162 (1 spcm.), 16165 (1 spcm.), 16166 (1 spcm.), 16167 (1 spcm.), 16168 (1 spcm.), 17336 (1 spcm.), 17337 (1 spcm.), 17338 (1 spcm.), 17339 (2 spcm.), 17340 (1 spcm.), 17341 (1 spcm.), 17342 (1 spcm.), 17343 (1 spcm.), 17344 (1 spcm.), 17345 (1 spcm.), 17346 (1 spcm.), 17347 (1 spcm.), 17376 (1 spcm.), 17377 (1 spcm.), 17378 (1 spcm.), 17379 (1 spcm.), 17380 (1 spcm.), 17381 (1 spcm.), 17382 (1 spcm.), 17383 (1 spcm.), 17384 (1 spcm.), 17385 (1 spcm.), 17386 (1 spcm.), 17387 (1 spcm.), 17388 (1 spcm.), 17389 (1 spcm.), 17782 (1 spcm.), 17783 (1 spcm.), 17784 (1 spcm.), 17785 (1 spcm.), 17786 (1 spcm.), 17787 (2 spcm.), 17788 (1 spcm.), 17789 (1 spcm.), 17790 (1 spcm.), 17791 (1 spcm.), 17792 (1 spcm.), 17793 (1 spcm.), 17794 (1 spcm.), 17795 (1 spcm.), 17796 (1 spcm.), 17797 (1 spcm.), 17798 (1 spcm.), 17799 (1 spcm.), 17800 (1 spcm.), 17801 (1 spcm.), 17802 (1 spcm.), 17803 (1 spcm.), 17804 (2 spcm.), 17805 (1 spcm.).

Stratigraphic occurrence. Layers B1 (5 spcm.), B2 (5 spcm.), C1 (3 spcm.), C2 (1 spcm.), D1 (7 spcm.). Moreover, 37 specimens are from excavation sites for which no profile is available, but, based on their height in the sediment and their preservation, it is possible to infer the layer of origin for some: 1 is likely from layer C1, 1 from C3, 12 from D, 3 from either B2 or C1, and 7 are from either C3 or D.

Description. Shell large, 4½ to 4¾ whorls, with depressed spire; shell length ~2/3 its width. Protoconch flattened, smooth; transition to teleoconch unclear. Teleoconch smooth, except for growth lines. Suture wellmarked. Body whorl slightly bent downwards near aperture; apertural region enlarged. Aperture prosocline, crescent-shaped, with strong callus; aperture length ~1/2 its width and ~1/2 shell length; aperture width ~1/2 shell width. Peristome markedly reflexed; thickened on basal and columellar regions. Umbilicus imperforate, with a marked callus formed by the peristome. On two specimens (BSPG 1959 II 16160 and 17339) it is possible to observe, under UV light, vestiges of three colored broad parallel spiral bands, the topmost one right below the carina, the other two regularly spaced on basal portion of whorl.

Measurements (in mm). BSPG 1959 II 16162 (deformed specimen; Figs. 10–13 ): H = 18.4; D = 26.0; h = 8.1; d = 14.3.

Previous identification of the material. Gall (1972: Nr. 19 and, in part, 20–21): respectively, Hemicycla asperula cf. leymerieana (Noulet), Cepaea silvana silvana (Klein) and Cepaea eversa larteti (Boissy) . Moser et al. (2009b: Nr. 64, in part, and 65): respectively, “ Cepaea ” sp. 1. and “ Cepaea ” sp. 2.

Discussion. The specimens from Sandelzhausen compare well with C. eversa , but are always larger, with half whorl more than typical C. eversa specimens. Moreover, the peristome of the present specimens is more reflected and only thickened on the basal and columellar regions, while typical C. eversa has the entire peristome thickened and not much reflected. Nevertheless, C. eversa seems to be a very variable species regarding shell morphology (Hír & Kókay 2004). It is also a very frequent species in Middle Miocene (MN 5–7) deposits of Central and Western Europe (Hír & Kókay 2004).

Figures

FIGURES 1 – 21. 1 – 2. Succinea minima (BSPG 1959 II 17471; H = 2.6 mm). 3 – 4. Palaeoglandina sp. (BSPG 1959 II 16145; H = 49.7 mm). 5. Testacella zelli (BSPG 1959 II 17689; H = 2.3 mm). 6 – 9. Klikia cf. c oarctata (BSPG 1959 II 16144; D = 9.3 mm). 10 – 13. Cepaea cf. eversa (BSPG 1959 II 16162; D = 26.0 mm). 14 – 17. Cepaea cf. sylvestrina (BSPG 1959 II 16156; D = 19.9 mm). 18 – 19. Tropidomphalus cf. incrassatus (BSPG 1959 II 456; D = 28.8 mm). 20 – 21. Tropidomphalus cf. incrassatus (BSPG 1959 II 457; D = 35.1 mm).