Hemiacirsa oscari

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 : 71

Hemiacirsa oscari (de Boury in Cossmann, 1912)

Figs 7H , 26H

Clathroscala (Hemiacirsa) lanceolata (Brocc.) — Boettger 1902: 88 (pars) [non Hemiacirsa lanceolata ( Brocchi, 1814) ]. Clathroscala (Hemiacirsa) lanceolata (Brocc.) — Boettger 1906: 98 (pars) [non Hemiacirsa lanceolata ( Brocchi, 1814) ]. Clathroscala (Hemiacirsa) prolanceolata Sacco— Boettger 1906: 98 (pars) [non Hemiacirsa prolanceolata ( Sacco, 1891) ]. Hemiacirsa Oscari De Boury —De Boury in Cossmann 1912: 196, pl. 6, fig. 10.

Acirsa (Hemiacirsa) oscari De Boury— Zilch 1934: 227 , pl. 10, fig. 65.

Acirsa (Hemiacirsa) oscari Boury— Korobkov 1955 : pl. 16, fig. 16.

non Acirsa (Hemiacirsa) oscari De Boury in Cossmann, 1912 — Bałuk 2006: 203, pl. 10, fig. 11 [= Pyrgostylus sp. ].

Type material. Holotype: SMF 380168 _12-1458 ( XII 1458 a), SL: 6.6 mm, MD: 2, 2 mm, CoŞteiu de Sus ( Romania), illustrated in Zilch (1934: pl. 10, fig. 65), Figs 7H , 26H .

Revised description. Small, moderately slender conical shell (apical angle 21°). Protoconch and early teleoconch whorls unknown. Teleoconch whorls strongly and evenly convex. Suture deeply incised, undulating. Sculpture of very prominent, opisthocline to opisthocyrt axial ribs separated by slightly wider interspaces (12: 11: 12). Spiral sculpture weak, of indistinct spiral cords. Last whorl attaining 40% of total height, faint basal angulation, base weakly convex, no peribasal cord, base with delicate axial ribs. Aperture ovate, Columella weakly concave. Outer lip not preserved. Basal lip thin. Columellar callus forming narrow rim. Umbilicus reduced to narrow chink.

Discussion. This species is placed in Hemiacirsa with some hesitation. It is squatter, with more convex whorls than most of its congeners. The species is slightly reminiscent of Cylindriscala de Boury, 1909 but lacks a well-defined basal disc. Hemiacirsa oscari is superficially reminiscent of Hemiacirsa drevermanni (de Boury in Cossmann, 1912) and Hemiacirsa abiaeformis sp. nov. in its prominent axial ribs but is less slender, lacks distinct spiral sculpture and has more convex whorls.

Paleoenvironment. Unknown.

Distribution in Central Paratethys. Badenian (Middle Miocene): Făget Basin: CoŞteiu de Sus ( Romania) ( Boettger 1902).

Figures

FIGURE 7. A. Anguloacrilla lima sp. nov., holotype, NHMW 1865/0001/0244, Lăpugiu de Sus (Romania). B. Anguloacrilla kimakowiczi (Boettger, 1896), NHMW 1876/0011/0081, Lăpugiu de Sus (Romania). C. Anguloacrilla schwarzhansi sp. nov., holotype, NHMW 2024/0279/0002, Grund (Austria). D. Anguloacrilla schwarzhansi sp. nov., paratype, NHMW 1859/0019/0109a, Porzteich (Czech Republic).E. Acirsa fusiformis sp. nov., holotype, NHMW 1873/0026/0043, Lăpugiu de Sus (Romania). G. Adiscoacrilla laticostata (Bałuk, 1975), holotype, Z.PAL.U.W., BkK-G 35, Korytnica (Poland). H. Hemiacirsa oscari (de Boury in Cossmann, 1912), holotype, SMF 380168_12-1458, CoŞteiu de Sus (Romania). I. Acirsa fusiformis sp. nov., paratype, NHMW 1873/0026/0043b, Lăpugiu de Sus (Romania). J. Adiscoacrilla anticoppii sp. nov., holotype, NHMW 2024/0279/0004, Grund (Austria). K. Adiscoacrilla herthae (Boettger, 1906), holotype, SMF 380169_12-1454, CoŞteiu de Sus (Romania). L. Adiscoacrilla walaszczyki sp. nov., holotype, NHMW 2024/0278/0002, Bad Vöslau (Austria).

FIGURE 26. A1–A2. Hemiacirsa miocenica (Seguenza, 1880), NHMW 1854/0035/0311, Lăpugiu de Sus (Romania). B1–B2. Hemiacirsa miocenica (Seguenza, 1880), NHMW 1863/0015/0202, Lăpugiu de Sus (Romania). C1–C2. Hemiacirsa miocenica (Seguenza, 1880), NHMW 1865/0001/0243, Lăpugiu de Sus (Romania). D1–D2. Hemiacirsa miocenica (Seguenza, 1880), BS.030.17.006, Tortonian, S. Agata (Italy). E1–E2. Hemiacirsa miocenica (Seguenza, 1880), NHMW 1867/0019/0254, CoŞteiu de Sus (Romania). F1–F2. Hemiacirsa miocenica (Seguenza, 1880), NHMW 2013/0078/0151, Baden-Sooss (Austria). G1–G2. Hemiacirsa miocenica (Seguenza, 1880), NHMW 1872/0030/0081, Baden-Sooss (Austria). H. Hemiacirsa oscari (de Boury in Cossmann, 1912), holotype, SMF 380168_12-1458, CoŞteiu de Sus (Romania).