Sthenorytis sthenorytoides ( Sacco, 1891 )

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 : 118

publication ID	https://doi.org/10.11646/zootaxa.5630.1.1
publication LSID	lsid:zoobank.org:pub:89462472-D932-4255-880F-C6EF15220A31
persistent identifier	https://treatment.plazi.org/id/03D787A4-FF90-FF91-FF3F-FD43FF5C9186
treatment provided by	Plazi
scientific name	Sthenorytis sthenorytoides ( Sacco, 1891 )
status

Treatment

Sthenorytis sthenorytoides ( Sacco, 1891) View in CoL

Figs 44A View FIGURE 44 1 –A View FIGURE 1 2 View FIGURE 2

* Cirsotrema? sthenorytoides Sacc.— Sacco 1891: 43 View in CoL , pl. 2, figs 5–6. Cirsotrema? sthenorytoides Sacco, 1891 View in CoL —Ferrero-Mortara et al. 1984: 45, pl. 5, fig. 7.

Type material. Lectotype (designated herein): BS.030.08.004 (stored in the Museo Regionale di Scienze Naturali Torino , Italy), Superga ( Italy), illustrated in Sacco (1891: pl. 2, fig. 5).

Illustrated material. Private collection, Anton Breitenberger (Bad Vöslau, Austria), SL: 29.8 mm, MD: 19.9 mm, Pernersdorf ( Austria), North-Alpine Foreland Basin; Figs 44A View FIGURE 44 1 –A View FIGURE 1 2 View FIGURE 2 .

Description. Shell very large, stocky, robust (apical angle ~52°), weakly coronate. Protoconch unknown. Early teleoconch whorls convex with close-set lamellae, faint spiral cords. Later teleoconch whorls with narrow, weakly concave subsutural ramp, weakly angled shoulder, moderately convex periphery placed just below mid-whorl. Suture deeply impressed. Sculpture of moderately close-set, prominent, strongly raised, weakly prosocline lamellae separated by wider interspaces, not aligned axially (19: 19: 13), not fused to lamellae on preceding whorl, weakly coronate along shoulder forming short trigonal spines. Crests of lamellae weakly rolled over. Two more prominent varices on last whorl with strongly rolled over crests. Axial interspaces with numerous delicate spiral cords. Last whorl attaining ~65% of total height, base sub-angled delimited by weak peribasal cord running up lamellae, base weakly convex, lamellae only slightly weaker over base, only slightly rolled over. Fasciole short, broad, with very prominent growth lines, separated from peristome by narrow chink. Aperture circular. Columella concave. Outer lip strongly thickened by varix. Columellar and parietal callus forming continuous, narrow rim, detached from base. Peristome very broad, duplex. No umbilicus.

Discussion. This species was described by Sacco (1891: 43) as Cirsotrema? sthenorytoides and is the type species of Pseudosthenorytis Sacco, 1891 [Peudostenorhytis is an incorrect subsequent spelling by Cossmann (1912: 51)]. Later, Pseudosthenorytis was treated as synonym of Cirsotrema Mörch, 1852 by Wenz (1938) and as synonym of Sthenorytis Conrad, 1863 by de Boury in Cossmann (1912: 51), Eames (1952: 50) and Clench & Turner (1950: 224). We follow de Boury in Cossmann (1912). Sthenorytis sthenorytoides ( Sacco, 1891) is slightly less depressed than many Sthenorytis species and has less prosocline axial ribs. Nevertheless, these features do not justify separation at genus level.

Paleoenvironment. At Pernersdorf channels formed in middle to outer neritic environments and were filled, with allochthonous assemblages uniting coastal-mudflat faunas with inner neritic ones (own data M.H.). The preservation suggests that the species was part of assemblages from inner neritic environments.

Distribution in Central Paratethys. Badenian (Middle Miocene): North Alpine -Carpathian Foreland Basin: Pernersdorf ( Austria (hoc opus).

Proto-Mediterranean Sea. Burdigalian (Early Miocene): Colli Torinesi : Superga, Albugnao ( Italy) ( Sacco 1891).