Leviathaniidae, Harzhauser & Schneider, 2014

Harzhauser, Mathias & Schneider, Simon, 2014, A new family of giant Jurassic-Cretaceous littorinoid gastropods from the northern Tethys shelf, Acta Palaeontologica Polonica 59 (2), pp. 367-378 : 369-372

Family Leviathaniidae nov.

Type genus: Leviathania Pčelincev, 1927 .

Diagnosis.—Large sized shells with gradate spire and globular last whorl with wide sutural ramp. Sculpture consisting of nodes, which are confined to the shoulder. In many species, the nodes are only present on the spire whorls, if developed at all, whilst a bulge-like keel appears on the last whorl. Sculpture may also be completely reduced to a keel-like shoulder. No axial sculpture known so far. Umbilicus phaneromphalous. The inner wall of the umbilicus has a strong concavity reflecting a central swelling of the inner lip; a weak anterior canal is present. Protoconch unknown.

Remarks.—The species attributed to Leviathania and its monogeneric family have usually been classified within the Purpurinidae Zittel, 1895 (e.g., Wenz 1939) or Purpuroideidae Guzhov, 2004 . The main argument for this assignment seems to have been the large last whorl and the angulated whorls. Kaim (2004) provided a revised diagnosis of the type genus of the Purpurinidae , which characterises members of this family as moderately sized with prominent axial and spiral sculpture. The umbilicus is reduced to a chink, which is covered by a thin inner lip. Numerous nominal species of Purpurina d’Orbigny, 1850 have been described by Eichwald (1868), Hudleston (1888), Brösamlen (1909), and Kaim (2004). The morphology of these taxa matches the diagnosis of Purpurina by Kaim (2004) and clearly excludes a close relation with the Leviathaniidae fam. nov. A revision of the family Purpurinidae Zittel, 1895 was presented by Guzhov (2004) who includes the genera Angularia Koken, 1892 , Eucycloidea Hudleston, 1888 , Moerckeia Böhm, 1895 , Pseudoscalites Kittl, 1894 , Purpurina d’Orbigny, 1850 , Tretospira Koken, 1892 , and Ptychostoma Laube, 1868 . Following earlier suggestions by Golovinova and Korotkov (1986), Guzhov (2004) doubted that Purpuroidea Lycett, 1848 and Leviathania Pčelintzev, 1927 can be maintained within that family and consequently introduced the new family Purpuroideidae for these genera. He based this family on “large or extremely large multispiral shells that lack an umbilicus and possess a siphonostomatous aperture bearing a short half-closed siphonal canal.” This diagnosis fits well to the numerous representatives of Purpuroidea Lycett, 1848 , as listed by Guzhov (2004), but obviously excludes Leviathania , which possesses a very distinct and deep umbilicus. Already Guzhov (2004) discussed the possibility that Leviathania should be removed from the Purpuroideidae but refrained from doing so due to the inadequate material known to him.

In the original description, Pčelincev (1927) considered this genus to be anomphalous. This misinterpretation might be explained by the fact that the gastropods are represented only by internal moulds consisting of the identical sediment as the umbilical filling. Therefore, the umbilical area differs hardly from the rest of the gastropod and appears to be closed at first sight. The character of the umbilicus is usually revealed only if cross sections are studied, allowing to trace the otherwise enigmatic shell outline.

Genus Leviathania Pčelincev, 1927

= Tuberleviathania Golovinova and Korotkov, 1986

= Turboleviathania Guzhov, 2004, lapsus calami pro Tuberleviathania )

Type species: Natica leviathan Pictet and Campiche, 1863 (the junior synonym of Strombus sautieri Coquand, 1856 ). Sainte-Croix (Kanton Waadt, Switzerland), “calcaire roux dans les marnes à bryozoaires” Pictet and Campiche 1863), Valanginian.

Species included: Leviathania gigantea ( Makowsky, 1874) , Tithonian, Czech Republic and Austria; Leviathania sp. , Tithonian or Berriasian, Ukraine; Leviathania sautieri ( Coquand, 1856) , Valanginian, Switzerland, France; Leviathania gerassimovi Pčelincev, 1927 , Valanginian, Caucasus; Leviathania subnodosa ( Roemer, 1836) , Kimmeridgian, Northern Germany ( Fig. 2 ). Doubtful species which probably belong to Leviathania , but are based on poorly preserved specimens: Leviathania sulcata Pčelincev, 1963 , Cretaceous, Crimea; L. sp., Tithonian, Crimea ( Korotkov 1989); L. beschterikensis Golovinova, 1982 , Cretaceous, Crimea; L. gabonensis ( Meunier, 1887) , Albian?, Gabon.

Diagnosis.—As given for family Leviathaniidae . If Tuberleviathania Golovinova and Korotkov, 1986 might be accepted as valid genus, the definition of Leviathania could be reduced to species with weak to obsolete nodes on the last whorls.

Discussion.—The species detailed below was usually placed in the genus Purpuroidea Lycett, 1848 . Purpuroidea is still used in a much too broad sense and needs revision as done by Kollmann (1984) for alleged Late Cretaceous representatives of that genus. In fact, this genus is based on the type species Murex ? nodulatus Young and Bird, 1828 from the Bathonian of England (note that Wenz [1939] erroneously mentioned Purpuroidea maureausea [ Buvignier, 1852] as type species). This species has a steep sutural ramp, blunt nodes and a rugose axial sculpture on the last whorl and develops a basal spiral cord. Its spire is high and coalescing. Other representatives of Purpuroidea , as described by Buvignier (1852) and Hudleston (1880), are also characterised by a moderately high spire and strong sculpture of the last whorl, which is bulbous naticoid. These morphologies have little in common with the huge shells from the Tithonian of Austria and the related specimens from Ukraine. In contrast, Leviathania Pčelincev, 1927 comprises large species with a gradate spire, smooth shell and anteriorly strongly expanding aperture. The sculpture is restricted to nodes or a keel along the shoulder. Its Valanginian type species is Natica leviathan Pictet and Campiche, 1863 , which is a junior synonym of Strombus sautieri Coquand, 1856 . Thus, it has to be referred to as Leviathania sautieri ( Coquand, 1856) .

Several species which have been assigned to Leviathania by Pčelincev (1927) and Golovinova (1982) from the Cretaceous of Russia have been transferred to Tuberleviathania Golovinova and Korotkov, 1986 , with the type species Leviathania gerassimovi Pčelincev, 1927 . Golovinova and Korotkov (1986) separated this genus from Leviathania based on the presence of nodes on the shoulder, the large size and the broad last whorl. The size and the width of the last whorl, however, are no distinguishing features. The size is even topped by some Leviathania species, as discussed below, and the broad last whorl is also developed in the type species of Leviathania , L. sautieri . Only the prominent nodes would be of interest, but there are also Tuberleviathania species with weakly developed nodes ( Guzhov 2004). Moreover, all taxa which have been assigned to Tuberleviathania in the literature are based on poorly preserved internal moulds and are rather dubious. Therefore, we follow Guzhov (2004) and treat Tuberleviathania Golovinova and Korotkov, 1986 tentatively as synonym of Leviathania .

Fig. 3. Littorinoid gastropod Leviathania gigantea ( Makowsky, 1874) → from the Tithonian of Dörfles , Lower Austria; in lateral (A 1 –C 1), ventral (A 2 –C 2), and dorsal (A 3 –C 3) views. A. Neotype NHMW2011 /0347/0001.

B. Reference specimen NHMW 2011/0264/0001. C. Reference specimen NHMW 2011/0347/0002.

Stratigraphic and geographic range.— Kimmeridgian to Valanginian: Portugal, Spain, France, Switzerland, Austria, Czech Republic, Germany, Ukraine, Crimea, Caucasus, Gabon ( Green 1934; Foucault 1971; Bosca 1922; Pictet and Campiche 1863; Makowsky 1874; Alth 1881, 1882; Pčelincev 1963, Golovinova 1982; Golovinova and Korotkov 1986; Meunier 1887).

Figures

Fig. 2. Schematic stratigraphic positions of the strata yielding species of Leviathania discussed in the text. Please note that lower and upper limits of most of these strata are tentative.