Cirsotrema schneideri, Harzhauser & Landau, 2025

Cirsotrema schneideri sp. nov.

Figs 19C View FIGURE 19 1 –C View FIGURE 1 2 View FIGURE 2

Cirsotrema crassicostanomala Sacco, 1891 View in CoL — Harzhauser et al. 2014: 92, pl. 3, figs 1a–1b [non

Cirsotrema crassicostanomalum ( Sacco, 1891) ].

Type material. Holotype, NHMW 2014 View Materials /0379/0032, SL: 33 mm, MD: 13.5 mm, Allerding ( Austria), Figs 19C View FIGURE 19 1 – C View FIGURE 1 2 View FIGURE 2 .

Type locality. Allerding ( Austria), North Alpine Foreland Basin .

Type stratum. Ottnang Formation

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

Etymology. In honor of Simon Schneider (CASP, Cambridge), in recognition of his contributions to Miocene paleontology.

Diagnosis. Very large, robust, slender shell with superficial suture, prominent subsutural collar and almost straight sided whorls, sculpture of broad varices with flat crests and five weaker spiral cords in deep, narrow axial interspaces.

Description. Shell very large, robust, slender (apical angle ~16°). Protoconch and early teleoconch whorls unknown. Early teleoconch whorls with broad varices and prominent spiral cords in axial interspaces, resulting in cancellate pattern. Later teleoconch whorls with prominent subsutural collar shallow subsutural concavity, weakly convex below mid-whorl. Suture fully obscured by varices. Sculpture of very broad, close-set, weakly prosocline, band-like flattened varices, not aligned axially, separated by deep, moderately narrow interspaces (?: 13: 14). Adapical tips of varices forming prominent subsutural collar. Deep interspaces with five prominent spiral cords. Last whorl attaining about 42% of total height, basal angulation delimited by broad, low peribasal cord, basal disc relatively narrow, varices weak on base with reduces spiral sculpture. Fasciole very short, broad with very prominent growth lines. Aperture subcircular. Columella concave. Outer lip slightly thickened by varix, basal lip broad. Columellar callus forming moderately broad rim, parietal callus thin, adherent. Peristome poorly preserved. No umbilicus.

Discussion. This species was erroneously identified by Harzhauser et al. (2014) as Cirsotrema crassicostanomalum ( Sacco, 1891) , from the Burdigalian of the Colli Torinesi ( Italy), due to comparable sculpture. However, Cirsotrema schneideri sp. nov. differs from C. crassicostanomalum in its much slenderer shell, the prominent subsutural collar and the very superficial suture. The same features distinguish it from the Pliocene Cirsotrema lamellosum ( Brocchi, 1814) and the Miocene Cirsotrema crassicostatum (Deshayes, 1850) .

Paleoenvironment. Agitated, rocky shore ( Harzhauser et al. 2014).

Distribution in Central Paratethys. Ottnangian (Early Miocene): North Alpine Foreland Basin: Allerding ( Austria).

Genus Clathroscala de Boury, 1890

Type species. Turbo cancellatus Brocchi, 1814 ; original designation by de Boury (1890: 215). Miocene, Italy.

Diagnosis. “ Shell fairly solid, though not very thick . Medium size ; elongated, conical shape; spire turriculate, not gradate, with convex, more or less regularly cancellate whorls, with punctations on the test between ribs; deep sutures, not bordered or canaliculated; axial ribs numerous, filiform, not lamellar, not deviated backwards on the sutures, often a little oblique, almost always interspersed with thicker, more widely flattened varices; these ribs are cut by spiral cords, fairly large and spaced apart. Last whorl equal to about a quarter of the total height, convex or subangular at the periphery of the base, which bears a fairly thick disc, often scalloped in outline between the ribs; this disc is concentrically furrowed and obscurely radiated by the trace of the ribs immersed in it; in the center, there is no trace of umbilicus or bead. Rounded aperture, with fairly thick peristome, devoid of auricle; the inner layer is very thin and continuous, the outer layer discontinuous, thin on the columellar edge, bordered by a varix on the labrum which is a little sinuous and sometimes slightly oblique to the vertical axis. ” (translated from Cossmann 1912: 70).

Discussion. This genus is known from a few Pliocene species from the Mediterranean Sea, northwestern Atlantic and the North Sea (e.g., Van Dingenen et al. 2016). The Middle Miocene Paratethyan Clathroscala xeniae ( Boettger, 1906) is the oldest member of the genus, followed by Clathroscala bureaui de Boury in Cossmann, 1912 and C. cancellata ( Brocchi, 1814) from the Late Miocene of France ( Landau et al. 2023).