Episcomitra hilberi ( Hoernes & Auinger 1880 ) Harzhauser & Landau, 2021

Harzhauser, Mathias & Landau, Bernard, 2021, The Mitridae (Gastropoda: Neogastropoda) of the Miocene Paratethys Sea, Zootaxa 4983 (3), pp. 1-72 : 12-13

Episcomitra hilberi ( Hoernes & Auinger 1880) nov. comb.

Figs 3G 1 –G 2 , H 1 –H 2

[ Mitra ] Hilberi nov. form.—Hoernes 1880: 125 [nomen nudum].

* Mitra Hilberi nov. form.— Hoernes & Auinger 1880: 76, pl. 9, figs 9–10.

M. [itra] Hilberi— Cossmann 1899: 156.

? Mitra hilberi Hoernes & Auinger an sp. dist.— Csepreghy-Meznerics 1956: 414, pl. 9, figs 15–17.

? Mitra hilberi pseudopolygyrata nov. var. — Strausz 1966: 363, pl. 12, figs 10–11.

Mitra hilberi Hoernes & Auinger, 1880 — Cernohorsky 1976: 377.

? Mitra hilberi var. pseudopolygyrata Strausz 1966 — Cernohorsky 1976: 377.

non Mitraria (Mitraria) hilberi ( Hoernes & Auinger, 1880) — Bałuk 2006: 215, pl. 14, fig. 8 [= Costellariidae ].

Type material. Lectotype (designated herein): NHMW 1865 /0015/0014, SL: 44.7 mm, MD: 11.8 mm, Jerutek at Lysice ( Czech Republic), Hoernes & Auinger (1880, pl. 9, fig. 9), figs 3H 1 –H 2 . Paralectotype: NHMW 1854 /0035/0100, SL: 30.1 mm , MD: 9.3 mm, Lăpugiu de Sus ( Romania), Hoernes & Auinger (1880, pl. 9, figs 10a–b), figs 3G 1 –G 2 .

Additional material. NHMW 1864 /0001/0445, 1 specimen, Drnovice u Vyškova ( Czech Republic) .

Revised description. Shell medium sized, slender fusiform with high spire and low last whorl. Protoconch unknown. About nine teleoconch whorls with narrow suture. Early teleoconch whorls weakly convex, periphery at mid-whorl. Sculpture consisting of six weak spiral cords fading out within fourth to fifth whorl. Last whorl low, weakly convex to subcylindrical with faint shoulder. Blurred spiral grooves between adapical suture and shoulder. Base moderately constricted with few spiral cords. Aperture wide, short, ovate. Columellar callus narrow, moderately thickened, sharply delimited; parietal callus not developed, bearing three prominent columellar folds, weakening abapically, with fourth subobsolete fold. Outer lip not preserved. Siphonal canal short, wide, weakly twisted with moderately deep siphonal notch.

Shell measurements and ratios (holotype). SL = 30.1 mm, MD: 9.3 mm, AA = 23°, A/S = 0.8, SL/ MD: 3.8, AL/AW: 3.8, AH/S: 2.3.

Discussion. Episcomitra hilberi is unique within Paratethyan Mitridae due to its high spire and low last whorl. The paratype from Lăpugiu de Sus ( Romania) is a subadult specimen, but agrees well with the holotype in shape and sculpture at a similar growth stage. The specimen from Hungary described by Csepreghy-Meznerics (1956) and Strausz (1966) as variety of M. hilberi ; Mitra hilberi pseudopolygyrata nov. var. is most probably conspecific. This name, however, is not available according ICZN Article 15.2., which states: “ A new name published after 1960 expressly as the name of a ‘variety’ or ‘form’ is deemed to be infrasubspecific and as such is not regulated by the Code ”.

The specimen from Korytnica ( Poland) identified as Mitraria hilberi by Bałuk (2006) differs in its small size and the presence of lirae within the outer lip, and rather represents a costellariid. Mitra megaspira Bellardi, 1887 , from the early Miocene of Italy, is the morphologically closest species from the European Neogene, but has a lower and broader spire and consequently a proportionately taller last whorl, and lacks spiral sculpture (see holotype in Ferrero-Mortara et al., 1981, pl. 46, figs 12a–b). Mitra agnata Bellardi, 1887 , from the middle Miocene of Italy (see holotype in Ferrero-Mortara et al., 1981, pl. 43, figs 2a–b), is reminiscent of E. hilberi but has a higher last whorl and lacks the prominent basal concavity.

Palaeoenvironment. Unknown. Probably middle to outer neritic environments.

Distribution in Central Paratethys. Badenian (middle Miocene): North-Alpine-Carpathian Foredeep: Jerutek at Lysice, Drnovice u Vyškova ( Czech Republic) ( Hoernes & Auinger 1880);? Pannonian Basin: Sámsonháza ( Hungary) ( Strausz, 1966); Făget Basin: Lăpugiu de Sus, Bujtur ( Romania).

Figures

FIGURE 1. A. Map of central and south–eastern Europe, representing the area that was partly covered by the Central Paratethys Sea (for detailed maps with the localities mentioned in the text see Kroh (2005) and Nosowska (2020). The white insert corresponds to the area that is restored in the palaeogeographic map below. B. Palaeogeography of the Middle Miocene Paratethys Sea (modified from Harzhauser & Landau 2017) showing the most important sedimentary basins (NAFB: North Alpine Foreland Basin, E–Sopr B: Eisenstadt–Sopron Basin).

FIGURE 2. Measurements for shell morphology and whorl profiles. SL: shell length, MD: maximum diameter, AA: apical angle, LWH: last whorl height, AH: aperture height. AL: aperture length. AW: aperture width. S: length of siphonal canal.

FIGURE 3. A1–A2. Episcomitra antibellardii nov. sp., holotype, Lăpugiu de Sus (Romania), NHMW 1854/0035/0100b. B1–B2. Episcomitra antibellardii nov. sp., paratype, NHMW 1854/0035/0100c. C1–C2. Episcomitra bouei (Hoernes & Auinger 1880), lectotype, Lăpugiu de Sus (Romania), NHMW 1854/0035/0100d. D1–D2. Episcomitra cochlearella (Mayer-Eymar, 1890), lectotype, Lăpugiu de Sus (Romania), NMB Inv. Nr. t3238). E1–E2. Episcomitra cochlearella (Mayer-Eymar, 1890), paralectotype, Lăpugiu de Sus (Romania), NMB Inv. Nr. t3238. F1–F2. Episcomitra facilis (Mayer-Eymar, 1890), holotype, Lăpugiu de Sus (Romania), Inv. Nr. t3308. G1–G2. Episcomitra hilberi (Hoernes & Auinger 1880), paralectotype, Lăpugiu de Sus (Romania), NHMW 1854/0035/0100. H1–H2. Episcomitra hilberi (Hoernes & Auinger 1880), lectotype, Jerutek at Lysice (Czech Republic), NHMW 1865/0015/0014. I1–I2. Episcomitra pilsbryi (Boettger, 1906), holotype, Coşteiu de Sus (Romania), SFM 360347 (= SFM XII 12.2207a).