Episcomitra leopoldiana, Harzhauser & Landau, 2021

Harzhauser, Mathias & Landau, Bernard, 2021, The Mitridae (Gastropoda: Neogastropoda) of the Miocene Paratethys Sea, Zootaxa 4983 (3), pp. 1-72 : 15-16

publication ID	https://doi.org/ 10.11646/zootaxa.4983.1.1
publication LSID	lsid:zoobank.org:pub:6A4778D6-195A-4AB1-AA1E-7D8000185B28
DOI	https://doi.org/10.5281/zenodo.5044169
persistent identifier	https://treatment.plazi.org/id/A82A87E9-8A18-3842-FF4D-FBE9FB3FFCB9
treatment provided by	Plazi
scientific name	Episcomitra leopoldiana
status	sp. nov.

Treatment

Episcomitra leopoldiana View in CoL nov. sp.

Figs 4A View FIGURE 4 1 –A View FIGURE 1 2 View FIGURE 2 , B 1 –B View FIGURE 1 2 View FIGURE 2 , C 1 –C View FIGURE 1 2 View FIGURE 2

Mitra Brusinae View in CoL nov. form.— Hoernes & Auinger 1880: 76, pl. 9, fig. 2 [non Episcomitra brusinai ( Hoernes & Auinger, 1880) View in CoL ]. M [itraria]. (M [itraria].) brusinae View in CoL (R. Hörn, et Au.)— Sieber 1958a: 153.

Mitraria View in CoL (M.) brusinae (R. Hörn. Auing.) View in CoL — Sieber 1958b: 149.

Mitraria (Mitraria) repleta (Bellardi, 1887) — Bałuk 1997: 32, pl. 8, fig. 9 [non Bellardi, 1887]

Type material. Holotype: NHMW 1846 View Materials /0037/0097a, SL: 46.1 mm, MD: 15.2 mm, Steinebrunn ( Austria), illustrated in Hoernes & Auinger (1880, pl. 9, fig. 2), figs 4A 1 –A 2 . Paratypes: NHMW 1846 View Materials /0037/0097b, SL: 40.8 mm , MD: 13.0 mm, Steinebrunn ( Austria), figs 4B 1 –B 2 ; NHMW 2020 View Materials /0131/0001, SL: 36.4 mm , MD: 12.7 mm, Steinebrunn ( Austria), figs 4C 1 –C 2 .

Additional material. NHMW 1846 View Materials /0037/0097, 15 specimens, Steinebrunn ( Austria) ; NHMW 1860 View Materials /0001/0120, 11 specimens, Mikulov ( Czech Republic) .

Type locality. Steinebrunn ( Austria), Vienna Basin .

Type stratum. Silty sand of the Baden Formation.

Age. Middle Miocene, Badenian.

Etymology. Referring to Leopold III (1073–1136), patron saint of Lower Austria, where the type locality is situated.

Diagnosis. Episcomitra species of moderately large size, moderately slender to moderately broad, with relatively high spire, weakly shouldered, subcylindrical spire whorls, spiral sculpture of flattish spiral cords on early spire whorls, distinctly weakening on penultimate and last whorls.

Revised description. Shell moderately large, moderately slender to moderately broad fusiform. Protoconch unknown. Teleoconch of nine whorls, suture distinctly incised. Early spire whorls weakly convex with periphery close to abapical suture; later spire whorls convex to subcylindrical, weakly shouldered. Incised suture gives somewhat swollen appearance to whorls despite generally weak convexity. Last whorl evenly convex, slowly contracting, with short base and shallow basal concavity. Sculpture consisting of six broad, flat spiral cords on early spire whorls, subsequently increasing in number by intercalations of secondary and tertiary spiral grooves, but becoming nearly obsolete on last three whorl. Weak spiral cords on base and fasciole. Aperture moderately narrow to moderately wide, elongate. Columellar callus distinct, narrow. Columella with four oblique columellar folds, abapically decreasing in strength. Outer lip thin. Siphonal canal moderately short, moderately wide with deep siphonal notch.

Shell measurements and ratios. SL = 36.4–46.1 mm, MD: 12.7–15.2 mm, AA = 35–37°, SL/MD: 3.0–3.1, AL/AW: 4.8–5.2, AH/S: 2.4–2.6.

Discussion. Bałuk (1997) recognized that the two specimens illustrated and described by Hoernes & Auinger (1880, pl. 9, figs 1 and 2) as Mitra brusinae were not conspecific. He therefore separated the specimen from Steinebrunn ( Figure 2 View FIGURE 2 of Hoernes & Auinger, 1880) and his material from Korytnica from Episcomitra brusinai , and identified it with the remark “ seem to be compatible ” as Mitraria repleta (Bellardi, 1887) . Episcomitra repleta (Bellardi, 1887) from the Pliocene of Asti ( Italy) (see holotype in Ferrero-Mortara et al., 1981, pl. 42, figs 12a–b) differs distinctly from the Paratethyan shells by its narrowly canaliculate suture, higher last whorl, longer aperture, cyrtoconoid spire, and less numerous but higher spire whorls. Moreover, it lacks spiral sculpture. Episcomitra oberrans (Bellardi, 1887) , from the late Miocene of Stazzano ( Italy), is highly reminiscent of E. leopoldina in size and shell shape, but is distinguished by its more convex spire whorls and the prominent spiral sculpture in the subsutural area (see Bellardi 1887a: 11, pl. 1 fig. 7). Episcomitra gravis (Bellardi, 1887) , from the late Miocene of Stazzano ( Italy), is another similar species, which differs in its conical instead of subcylindrical spire whorls (see Bellardi 1887a: 10, pl. 1 fig. 6).

Palaeoenvironment. Shallow neritic.

Distribution in Central Paratethys. Badenian (middle Miocene): Vienna Basin: Steinebrunn ( Austria), Mikulov ( Czech Republic) ( Hoernes & Auinger 1880); Korytnica Basin: Korytnia ( Poland) ( Bałuk 1997).