Cirsotrema pollerspoecki, Harzhauser & Landau, 2025

Harzhauser, Mathias & Landau, Bernard M., 2025, The Epitoniidae (Gastropoda, Epitonioidea) of the Miocene Central Paratethys Sea-an overwhelming diversity, Zootaxa 5630 (1), pp. 1-142 : 49-50

Cirsotrema pollerspoecki sp. nov.

Figs 19A–B

Cirsotrema (Cirsotrema) miovaricosum Sacco, 1891 — Steininger 1973: 406 [non Cirsotrema miovaricosum ( Sacco, 1891) ]. Cirsotrema miovaricosum Sacco, 1891 — Schneider et al. 2009: 74, figs 5b–c [non Cirsotrema miovaricosum ( Sacco, 1891) ].

Type material. Holotype, BSPG 2007 X 110, SL: 4.4 mm, MD: 2.8 mm, Gurlan ( Germany), illustrated in Schneider et al. (2009: fig 5b), Fig. 19A . Paratype, BSPG 2007 X 111, SL: 3.0 mm , MD: 2.5 mm, Gurlan ( Germany), illustrated in Schneider et al. (2009: fig 5c), Fig. 19B . Stored in Bayerische Staatssammlung für Paläontologie und Geologie, Munich ( Germany) .

Type locality. Gurlan ( Germany), North Alpine Foreland Basin .

Type stratum. Upper Marine Molasse .

Age. Early Miocene, early Ottnangian (mid-Burdigalian).

Etymology. In honor of Jürgen Pollerspöck (Zoologische Staatssammlung München) in recognition of his contributions on paleoichthyology.

Diagnosis. Small, moderately slender shell with convex whorls, deeply incised suture, faintly coronate shoulder, very prominent, close-set, moderately broad, prosocline, internally lamellose varices, five prominent spiral cords in interspaces, narrow peribasal cord and wide basal disc.

Description. Small, moderately slender (apical angle ~25°). Protoconch and early teleoconch whorls unknown. Teleoconch whorls convex with deeply impressed suture, narrow subsutural shelf with faintly coronate shoulder. Very prominent, close-set, moderately broad, prosocline, internally lamellose varices separated by deep, slightly wider or narrower interspaces with five prominent spiral cords. Three more prominent varices on last whorl. Last whorl with marked basal angulation delimited by narrow peribasal cord, wide basal disc, varices but narrowing prominent on base. Fasciole short, broad, with strong growth lines. Aperture subcircular. Columella concave. Outer lip and basal lip strongly thickened. Columellar and parietal callus forming narrow, continuous rim, detached from base. Peristome strongly thickened, duplex. No umbilicus.

Discussion. Schneider et al. (2009) illustrated two fragments, identified by these authors as Cirsotrema miovaricosum ( Sacco, 1891) . However, the holotype of C. miovaricosum , from the Tortonian of S. Agata ( Italy), differs in its much narrower varices and the cancellate sculpture (see Ferrero-Mortara et al. 1984: pl. 5, figs 16a–b). Cirsotrema crassicostatum (Deshayes, 1850) [including Cirsotrema thais de Boury in Cossmann, 1912, as illustrated in Cossmann (1912)] differs in the less convex whorls, broader subsutural shelf and the fewer and less prosocline varices (see Cossmann 1912: pl. 3, figs 1–3, pl. 6, fig. 16). Cirsotrema subsequenzai ( Sacco, 1891) , from the Tortonian of S. Agata ( Italy) is reminiscent of Cirsotrema pollerspoecki sp. nov. in whorl profile and sculpture but differs in its broader varices, and it lacks a basal angulation with peribasal cord (see Sacco 1891: pl. 2, fig. 17).

Cirsotrema pollerspoecki sp. nov. is reminiscent of the Middle Miocene Cirsotrema hornesi ( De Gregorio, 1889) but its varices are not fused and differs in its weaker peribasal basal cord and wider basal disc.

Paleoenvironment. Agitated rocky shore and coastal environments ( Schneider et al. 2009).

Distribution in Central Paratethys. Ottnangian (Early Miocene): North Alpine Foreland Basin: Gurlan ( Germany) ( Schneider et al. 2009), Reinbach at Schärding ( Austria) ( Steininger 1973).

Figures

FIGURE 19.A. Cirsotrema pollerspoecki sp. nov., holotype, BSPG 2007 X 110, Gurlan (Germany).B. Cirsotrema pollerspoecki sp. nov., paratype, BSPG 2007 X 111, SL: 3.0 mm, MD: 2.5 mm, Gurlan (Germany). C. Cirsotrema schneideri sp. nov., holotype, NHMW 2014/0379/0032, Allerding (Austria).