Sigaretotrema sp.

Sigaretotrema sp.

Figs 60A View FIGURE 60

1

–A

View FIGURE 1

2 View FIGURE 2

Sigaretus aquensis Récl. View in CoL var.— Schaffer 1912: 167, pl. 54, figs 19 [ non Sigaretus aquensis Récluz, 1851 View in CoL = Sinum patulum ( Grateloup, 1845) View in CoL ].

Sinum patulum (Grateloup 1847) View in CoL — Pfister & Wegmüller 2007: 103, pl. 19, figs 8–21 [ non Sinum patulum ( Grateloup, 1845) View in CoL ].

Illustrated material. NHMW 1860/0050/0375, SL: 13.1 mm, MD: 13.5 mm, Gauderndorf ( Austria), illustrated in Schaffer (1912: pl. 54, fig. 19), Figs 60A View FIGURE 60 1 –A View FIGURE 1 2 View FIGURE 2 .

Additional material. 2 spec., NHMW 1851 View Materials /0006/0026, Gauderndorf ( Austria) .

Revised description. Small, moderately depressed shell of about two teleoconch whorls, with conical spire; apical angle 120°, wider than high ( SL /MD = 0.97). Protoconch unknown. Suture narrowly incised. Sculpture of first teleoconch whorl of>20 narrow, convex to flattish spiral cords of subequal width, separated by slightly narrower interspaces. Growth lines insignificant to weak. Last whorl moderately expanding, with very broad, convex subsutural ramp, convex periphery placed distinctly below mid-whorl. Last whorl attaining 97% of total height. Aperture wide, ovate, strongly prosocline, attaining 90% of total height. Base and aperture obscured by sediment.

Discussion. This species is characterized by its regular spiral sculpture of subequal cords, which distinguishes it from Sigaretotrema exclathratum ( Sacco, 1891) and the much larger Sigaretotrema vindobonensis nov. sp. Although we assume that this is a yet undescribed species, the preservation is too poor to allow a clear characterization. Sigaretotrema michaudi ( Michelotti, 1847) , from the Rupelian and Burdigalian of Italy, is comparable in shape and size but has narrower and more numerous spiral cords ( Robba et al. 2016: pl. 14, fig. 9).

Paleoenvironment. Inner neritic, coastal marine sandy environments (own data M.H.).

Distribution in Central Paratethys. Eggenburgian (Early Miocene): North Alpine-Carpathian Foreland Basin: Belpberg, Längenberg, Rüschegg ( Switzerland) ( Pfister & Wegmüller 2007); Gauderndorf ( Austria) ( Schaffer 1912).

Genus Sinum Röding, 1798

Type species. Helix haliotoidea Linnaeus, 1758 ; subsequent designation by Dall (1915: 109). Present-day, Indo-West Pacific.