Contortia callosa (Hörnes, 1854) Harzhauser & Landau, 2012

Harzhauser, Mathias & Landau, Bernard, 2012, A revision of the Neogene Cancellariid Gastropods of the Paratethys Sea 3472, Zootaxa 3472, pp. 1-71 : 21-23

Contortia callosa (Hörnes, 1854) nov. comb.

Figs 3J, 5E 1–E 3, 5F 1–F 3, 5G 1–G 3

Cancellaria callosa Partsch — Hörnes 1848: 19 (nomen nudum).

Cancellaria callosa Partsch —Hörnes 1854: 314, pl. 34, figs. 14–16 [ex Partsch MS.].

Cancellaria callosa Partsch — Hoernes & Auinger 1890: 274.

Cancellaria callosa Ptsch ,— Boettger 1902: 38.

Cancellaria (Merica) callosa Partsch — Sieber 1936: 79.

Cancellaria (Merica) callosa Ptsch. — Sieber 1956: 245.

? Cancellaria (Merica) callosa Partsch — Hölzl 1973: 172.

Cancellaria (Merica) callosa Partsch, 1856 — Bałuk 2006: 214, pl. 16, fig. 1 [note that the authorship “Partsch” refers to a mansucript name].

non Merica callosa Partsch — Friedberg 1928: 577, pl. 37, fig. 21.

Type material. NHM Vienna ( Austria); see below for details .

Studied material. 1 spec. Gainfarn ( Austria) NHMW 2009 z0098/0014; 2 spec. Steinebrunn ( Austria) NHMW 2009 z0098/0015, NHMW 1863 /0015/0696; 1 spec. Niederleis ( Austria) NHMW 1863 /0020/0696; 2 spec. Forchtenau ( Austria) NHMW 1866 /0001/1082; 4 spec. Lăpugiu de Sus ( Romania) NHMW 1854 /035/0233; 2 spec. CoŞteiu de Sus ( Romania), NHMW 1867 /0029/0128.

Illustrated material. Fig. 3J: CoŞteiu de Sus ( Romania), height: 29.2 mm, width: 17.8 mm, NHMW 1867 / 0029/0128. Figs. 5E 1–E 3: syntype illustrated in Hörnes (1854, pl. 34, figs 14a–b), Gainfarn ( Austria), height: 33.6 mm, width: 22.7 mm, NHMW 2009 z0098/0014. The specimen is marked with a 14, which indicates that it is the specimen figured by Hörnes. This is usually a reliable marker, and it therefore seems that the illustration was strongly idealised. Figs 5F 1–F 3: specimen illustrated in Hörnes (1854, pl. 34, figs 15a–b), Steinebrunn ( Austria), height: 26.9 mm, width: 18.9 mm, NHMW 2009 z0098/0015. Figs 5G 1–G 3: specimen illustrated in Hörnes (1854, pl. 34, figs 16a–b), Steinebrunn ( Austria), height: 20.2 mm, width: 13.5 mm, NHMW 1863 /0015/0696.

Discussion. This bulky shell is characterized by an inflated shell and globose last whorl. It develops c. 10–12 blunt axial ribs, which are crossed by a spiral sculpture consisting of numerous spiral threads and few broader primary spirals. These are formed by 2–3 close-spaced spiral threads and amalgamate into a single band especially on the backs of the axial rib. Insignificant growth lines cross the spiral threads and cause a somewhat irregular and finely incised surface of the spirals. The protoconch is available only from a single slightly abraded specimen and suggests a low low dome-shaped morphology consisting of about 2.5 weakly convex whorls with a depressed initial part. The absence of a sutural ramp, the convex whorls, the weak to absent umbilicus, the predominant axial sculpture and the presence of three columellar folds are characteristic for the genus Contortia Sacco, 1894 as defined by Cahuzac et al. (2004) and Landau et al. (2006).

The Burdigalian shells from the Colli Torinesi in Italy, treated by Sacco (1894) as Contortia callosa taurolaevior and C. c. tauroturrita, differ strongly from the type in their sculpture. They lack the characteristic spiral cords and have broader and poorly defined axial ribs .

Distribution. This species is always rare but was distributed throughout the entire Paratethys. Recently, Landau et al. (in prep.) also found Contortia callosa from the late Middle Miocene or earliest Late Miocene of the Karaman Basin in Turkey, extending the distribution area of the species into the Proto –Mediterranean Sea.

The record from Bavaria mentioned by Hölzl (1973) would extend the range down to the Early Miocene. This record, however, is only given in a list without any description and has to be treated with caution.

Paratethys —Badenian: North Alpine Foreland Basin ( Austria: Niederleis); Polish–Carpathian Foredeep ( Poland: Korytnica); Vienna Basin ( Austria: Gainfarn, Steinebrunn); Eisenstadt–Sopron Basin ( Austria: Forchtenau); Transylvanian Basin ( Romania: Lăpugiu de Sus, CoŞteiu de Sus). Proto –Mediterranean Sea —Late Serravallian or Early Tortonian: Karman Basin ( Turkey).