Hemiacirsa drevermanni

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 : 66-67

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-FFA4-FFA6-FF3F-F8B0FA8692A7
treatment provided by	Plazi
scientific name	Hemiacirsa drevermanni
status

Treatment

Hemiacirsa drevermanni (de Boury in Cossmann, 1912)

Figs 24C View FIGURE 24 , 25A–D View FIGURE 25

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) ].

* Acirsa (Hemiacirsa) Drevermanni de Boury — De Boury in Cossmann 1912: 196, pl. 6, figs 4–6.

Acirsa (Hemiacirsa) drevermanni De Boury — Zilch 1934: 227 , pl. 10, fig. 66.

Acirsa (Hemiacirsa) drevermanni Boury— Korobkov 1955 : pl. 16, figs 14–15.

Acirsa (Hemiacirsa) drevermanni Boury in Cossmann 1912 — Kojumdgieva in Kojumdgieva & Strachimirov 1960: 94, pl. 30, fig. 3.

Type material. Holotype, SMF 380167 About SMF _12-1459 ( XII 1459 a), SL: 7.5 mm, MD: 2.0 mm, CoŞteiu de Sus ( Romania), specimen illustrated in Zilch (1934: pl. 10, fig. 66), Fig 25A View FIGURE 25 .

Illustrated material. NHMW 2018/0248/0552a, SL: 7.7 mm, MD: 2.0 mm, CoŞteiu de Sus ( Romania), Figs 24C View FIGURE 24 , 25D View FIGURE 25 1 –D View FIGURE 1 2 View FIGURE 2 . NHMW 2018/0248/0552b, SL: 7.3 mm, MD: 2.2 mm, CoŞteiu de Sus ( Romania), Figs 25B View FIGURE 25 1 –B View FIGURE 1 2 View FIGURE 2 . NHMW 2018/0248/0552c, SL: 6.7 mm, MD: 1.7 mm, CoŞteiu de Sus ( Romania), Figs 25C View FIGURE 25 1 –C View FIGURE 1 2 View FIGURE 2 .

Additional material. 10 spec., NHMW 2018 View Materials /0248/0552c, CoŞteiu de Sus ( Romania) .

Revised description. Shell small, slender conical (apical angle ~15–18°). Protoconch with cyrtoconoidal outline, elevated blunt nucleus (diameter 280 μm); slender, turreted spire of 4.5 smooth, weakly convex whorls, last whorl with weak angulation just below mid-whorl. Teleoconch of eight whorls, with very steep, weakly concave subsutural ramp, and weakly convex periphery placed distinctly below mid-whorl. Suture weakly impressed, linear or slightly undulating. Sculpture of moderately close-set, convex, orthocline to weakly opisthocline axial ribs, not aligned axially (10/12: 10/11: 10/12), separated equal width to slightly wider interspaces, bearing about eight prominent, broad spiral cords, forming more or less prominent rectangular pattern. Slightly more prominent subsutural cord and prominent spiral cord at abapical suture may occur. Last whorl attaining 35% of total height, axial ribs terminate abruptly at weakly rounded basal angulation delimited by up to three moderate strength peribasal cords. Base weakly convex with about five weak spiral cords. Aperture elongate ovate, columella weakly convex. Outer lip and basal lip thin. Columellar callus forming narrow rim, weakly detached from base, parietal callus delicate. Peristome simple. Umbilicus reduced to narrow chink.

Discussion. Hemiacirsa drevermanni (de Boury in Cossmann, 1912) exhibits some variability in the number of axial ribs, strength of the spiral cords, and strength of the peribasal cords. Typical specimens are characterized by the elongate rectangular sculpture. Hemiacirsa superelongata sp. nov. develops comparable spiral sculpture but differs in its much slenderer outline and blurred axial ribs. Hemiacirsa miocenica ( Seguenza, 1880) is larger and has broader and more numerous spiral cords.

Paleoenvironment. Unknown.

Distribution in Central Paratethys. Badenian (Middle Miocene): Făget Basin: CoŞteiu de Sus ( Romania) ( Boettger 1902); Dacian Basin: Opanec ( Bulgaria) (Kojumdgieva in Kojumdgieva & Strachimirov 1960).