Helicodontidae

Salvador, Rodrigo Brincalepe, 2013, The fossil pulmonate snails of Sandelzhausen (Early / Middle Miocene, Germany): Succineidae, Testacelloidea and Helicoidea, Zootaxa 3721 (2), pp. 157-171 : 166-169

Helicodontidae indet.

( Figs. 24–25 )

Material examined. BSPG 1959 II 17300 (1 spcm.).

Stratigraphic occurrence. Layer D1.

Description. Shell diminutive, seemingly planispiral; whorls regularly increasing in width and height. Protoconch (1¼ whorl) blunt, smooth; transition to teleoconch unclear. Teleoconch sculptured by regularly distributed fine vertically elongated scales. Spire flat. Suture well-marked. Umbilicus apparently narrow.

Measurements (in mm). Incomplete specimen; 2¼ whorls; H = 2.0; D = 3.7.

Previous identification of the material. Gall (1972: Nr. 12): Helicodonta (Helicodonta) involuta scabiosa (Sandberger) . Moser et al. (2009b: Nr. 57):? Protodrepanostoma sp.

Discussion. As only the first whorls are preserved it is very hard to offer a more precise classification. The overall profile of the shell, with a completely flat spire and a strong carina, as well as the sculpture pattern with papillae, is consistent with the helicodontids. However, the specimen from Sandelzhausen is somewhat unusual: its whorls are not as closely packed as is the rule for the family and it seems to have a much narrower umbilicus. Hence, the classification of previous authors in either Protodrepanostoma Germain or Helicodonta Férussac does not seem appropriate.

Remarks. As indicated in Helicidae indet. above, the two other helicodontids indicated by Moser et al. (2009b: Nr. 58 and 59; respectively,? Helicodontidae fam., gen. et sp. indet. 1 and 2) actually are helicid spire tops, which can be seen by the shape and size of the protoconch and the shape of the later whorls.

Family Hygromiidae

Genus Leucochroopsis O. Boettger

Leucochroopsis kleinii (Klein, 1847) ( Figs. 26–27 )

Helix kleinii Klein, 1847: 69 (pl. 1, fig. 8). Trichia (Leucochroopsis) kleini kleini [sic]: 429. Leucochroopsis kleini kleini [sic]: Gall, 1972: 9. Klikia (Apula) sp.: Gall, 1972: 10.

Material examined. BSPG 1959 II 16147 (1 spcm.), 17314 (3 spcm.), 17315 (3 spcm.), 17316 (14 spcm.), 17317 (2 spcm.), 17470 (1 spcm), 17472 (1 spcm.), 17475 (1 spcm.), 17722 (1 spcm.), 17723 (1 spcm.), 17724 (1 spcm.), 17725 (1 spcm.), 17726 (1 spcm.),.

Stratigraphic occurrence. Layers C (2 spcm.) and D1 (22 spcm.). The other specimens stem from samples for which no profile is available, but based on their height in the sediment and their preservation, 3 likely come from layer C3, 2 from D1, 1 from either B or C, and 1 from C or D1.

Description. Shell small, with a depressed conical spire and a rounded inferior portion. Protoconch (~1¼ whorl) large, blunt, smooth; transition to teleoconch unclear. Teleoconch sculptured by fine regularly distributed well-marked papillae; growth lines sometimes more marked. Whorls’ profile convex. Suture well-marked, but not too deep. Whorls regularly increasing in size. Whorls with a smooth keel-like angulation. Aperture apparently crescent-shaped and slightly prosocline. Umbilicus apparently rimate.

Measurements (in mm). 4 whorls (all specimens are juvenile); H = ~4.0; D = ~6.3.

Previous identification of the material. Gall (1972: Nr. 11 and 17): respectively, Leucochroopsis kleini kleini [sic] (Klein) and Klikia (Apula) sp. Moser et al. (2009b: Nr. 55, 60 and 63): respectively, Soosia sp., Trichiopsis sp. and Hygromiidae gen. indet. sp. 3.

Discussion. Leucochroopsis kleinii is known from the Middle Miocene of the Silvanaschichten, Germany, to the Late Miocene of Vienna Basin (Klein 1847; Schlickum 1976; Harzhauser & Binder 2004). Although the status of the genus and of its species has been recently called into question (Moser et al. 2009b), the specimens from Sandelzhausen compare fittingly with Klein’s original material from the Silvanaschichten (housed at the SMNS), which are approximately of the same age. The more poorly preserved specimens were identified as distinct species by previous authors (Gall 1972; Moser et al. 2009b), but their size, protoconch shape and teleoconch sculpture are all indicative of L. kleinii .

Genus Urticicola Lindholm

Urticicola perchtae sp. nov. ( Figs. 28–32 )

Hygromiidae gen. indet. sp. 2: Moser et al., 2009b: 50.

Leucochroopsis sp.: Böttcher et al., 2009: 241 (figs. 13–14).

Type material. Holotype: BSPG 1959 II 17312 ( Figs. 28–29, 32 ). Paratype: BSPG 1959 II 17313 (1 spcm.; Figs. 30–31 ).

Etymology. Perchta (or Berchta) is a Germanic goddess from the Alpine region (including Bavaria), probably derived from the ancient Celtic Lady of the Beasts and being a southern counterpart of the northern German Holda (Grimm, 1882; Motz, 1984). Although her image was much deteriorated under Christian influence (to the point of becoming a simple evil spirit or witch), she was originally a goddess of winter, spinning and beasts and was said to wear a beautiful white garb, her name meaning “the bright one” (Grimm, 1882; Motz, 1984). It seems an appropriate name for this Bavarian fossil, which is bright white with a delicate sculpture as its “garb”.

Type locality. Sandelzhausen, Mainburg, Germany; 48º37’36.9” N, 11º48’11.6”E; 493 m height.

Stratigraphic occurrence. Layer D1.

Age: Middle Miocene, Burdigalian/Langhian boundary (early middle MN5 European Mammal Neogene zone; 16.47 or 16.27 Ma; Moser et al. 2009a).

Diagnosis. Shell small, umbilicated; suture deep; whorls convex, with keel-like angulation.

Description. Shell small, depressed; whorls regularly increasing in size. Protoconch (~1¼ whorl) blunt, sculptured by very fine axial striae and scattered knobs near the suture; transition to teleoconch unclear. Teleoconch sculptured by regularly distributed and vertically-elongated fine scales; portion near suture sculptured by fine axial striae. Whorls’ profile convex. Suture well-marked, deep. Whorls with a smooth but prominent keel-like angulation. Umbilicated.

Measurements (in mm). Holotype: 3 whorls; H = 3.5; D = 2.1. Paratype: 2½ whorls; H = 2.9; D = 1.9.

Previous identification of the material. Moser et al. (2009b: Nr. 62): Hygromiidae gen. indet. sp. 2.

Discussion. Urticicola was previously considered a subgenus of Zenobiella Gude & Woodward , but is now regarded as a separate entity based on its shell sculpture (with scale-like structures), a broader umbilicus and a more pronounced keel (Welter-Schultes 2012). The name Urticicola was originally described as a subgenus and its grammatical gender was not stated. Manganelli et al. (1995) claimed that this name and most names ending in “- cola” have been traditionally regarded as feminine. However, Welter-Schultes (2012) argues that it should be considered masculine under the Art. 30.1.4.2 of the ICZN.

Urticicola perchtae is the first fossil record of the genus (fossil Zenobiella are known from the Pleistocene; Zilch 1959–1960). It is very similar to the Recent U. glabellus (Draparnaud) from Eastern France, differing by its smaller size, a deeper suture and more convex whorls, giving its spire a profile similar to a step pyramid. Moreover, it differs from the Recent central European species U. umbrosus (Pfeiffer) by its more rounded profile, a higher body whorl and a narrower umbilicus. Unfortunately, only two juvenile specimens were found in Sandelzhausen and thus a description of the apertural region is presently not possible.

Remarks. A careful examination of the original material studied by Böttcher et al. (2009: figs. 13–14) revealed that their so-called Leucochroopsis sp. (SMNS 68657) is actually a specimen of U. perchtae . Their material stems from the locality of Oggenhausen 2, in southern Germany, and is coeval with Sandelzhausen (MN5).

Figures

FIGURES 22 – 32. 22 – 23.? Helicodonta sp. (BSPG 1959 II 17678; D = 4.3 mm). 24 – 25. Helicodontidae indet. (BSPG 1959 II 17300; D = 3.7 mm). 26 – 27. Leucochroopsis kleinii (BSPG 1959 II 16147; D = 5.0 mm). 28 – 29. Urticicola perchtae sp. nov. (holotype; BSPG 1959 II 17312; H = 3.5 mm). 30 – 31. Urticicola perchtae sp. nov. (paratype; BSPG 1959 II 17313; H = 2.9 mm). 32. Urticicola perchtae sp. nov., protoconch detail (holotype; BSPG 1959 II 17312).