Mitrella, Risso, 1826

Harzhauser, Mathias & Landau, Bernard M., 2021, The Columbellidae (Gastropoda, Buccinoidea) in the Miocene Paratethys Sea — striking diversity of a negelected group, Zootaxa 5025 (1), pp. 1-75 : 35-37

“ Mitrella ” bittneri ( Hoernes & Auinger, 1880)

Figs 4U, 12A 1 –A 2 , B 1 –B 2 , C 1 –C 2

[ Mitrella ] Bittneri nov. form.—Hoernes 1880: 127 [nomen nudum].

* Columbella (Mitrella) Bittneri nov. form.— Hoernes & Auinger 1880: 98, pl. 12, figs 4a–c.

Columbella (Mitrella) bittneri Hö. Au. — Boettger 1902: 17.

Columbella (Mitrella) bittneri Hö. Au. — Boettger 1906: 17.

Mitrella Bittneri Hörn u. Auing.— Meznerics 1933: 341.

Pyrene (Mitrella) bittneri Hoernes et Auinger — Csepreghy-Meznerics 1956: 403, pl. 7, figs 14–15.

P.[yrene]. (P [yrene].) bittneri (R. Hörn. et Au.) — Sieber 1958a: 147.

Pyrene (P [yrene].) bittneri (R. Hörn. Au.) — Sieber 1958b: 148.

Pyrene (Mitrella) bittneri Hoernes & Auinger 1880 —Kojumdgieva in Kojumdgieva & Strachimirov 1960: 183, pl. 45, figs 4–5.

Pyrene (Mitrella) bittneri Hoernes & Auinger, 1880 — Strausz 1966: 290, pl. 42, figs 25–28.

? Mitrella (Mitrella) bittneri (R. Hoernes et M. Auinger, 1880) — Švagrovský 1981: 145, pl. 45, fig. 9.

Mitrella (Mitrella) bittneri ( Hoernes & Auinger, 1880) — Atanacković 1985; 143, pl. 32, figs 7–8.

Pyrene (Mitrella) bittneri ( Hoernes & Auinger, 1880) — Bałuk 1995: 235, pl. 32, figs 5–6.

Type material. Lectotype (designated herein): NHMW1860 /0001/0129a, SL: 8.0 mm, MD: 3.4 mm, Steinebrunn ( Austria), illustrated in Hoernes & Auinger (1880, pl. 12, fig. 4), Figs 4U, 12A 1 –A 2 . Paralectotypes: NHMW1860 / 0001/0129b, SL: 8.7 mm, MD: 3.8 mm, Steinebrunn ( Austria) , Figs 12B 1 –B 2 . NHMW1860 /0001/0129c, SL: 8.3 mm, MD: 3.4 mm, Steinebrunn ( Austria) , Figs 12C 1 –C 2 . NHMW1860 /0001/0129, 230 spec., Steinebrunn ( Austria) .

Additional material. NHMW2020 /0172/0006 (ex B. Landau coll.), 3 spec., Lăpugiu de Sus ( Romania) .

Description. Shell moderately small, moderately broad ovoid, with narrowly incised suture. Protoconch depressed conical of 3.5 convex whorls. Early protoconch whorls low; last protoconch whorl higher with periphery at abapical suture. Teleoconch of five whorls. Transition from first to second teleoconch whorl marked by somewhat allometric increase in width resulting in slightly oblique suture.Later spire whorls high, weakly convex with periphery at abapical suture. Last whorl high, ovoid, rounded to subobsoletely angular at periphery, slowly contracting. Shell surface smooth, except for fine cords over siphonal fasciole. Aperture moderately narrow. Outer lip moderately to strongly thickened internally by labial callus pad extending along inner edge of mid-portion of outer lip, with eight prominent denticles within; D2 strongest. Anal canal moderately broad, V-shaped. Siphonal canal moderately short and wide, slightly deflected, deeply notched at tip. Columellar callus moderately thickened, sharply delimited from base, abruptly terminating at adapical end of siphonal canal, with about five poorly defined denticles. Parietal callus narrow, thin, adherent

Shell measurements and ratios. SL: 8.0– 8.7 mm, MD: 3.4–3.8 mm, AA: 42–45°, SL/MD: 2.3–2.5, AL/AW: 3.6–4.3, LWH/AH: 1.3–1.4.

Discussion. This species is slightly reminiscent of Pyreneola Iredale, 1918 (type species Columbella abyssicola Brazier, 1877 ; present-day, Australia). Especially the low dome-shaped protoconch with a pointed apex is also seen in the extant species Pyreneola cincinnata (von Martens, 1880) , P. delineata ( Thiele, 1925) , P. lozoueti Drivas & Jay, 1997 , P. martae Monsecour & Monsecour, 2018 , P. melvilli ( Hedley, 1899) and P. tuamotuensis Monsecour & Monsecour, 2018 (see Drivas & Jay 1997, figs 17/18–21; deMaintenon 2008, figs 25–26; Monsecour & Monsecour, 2018, pl. 4, figs Q–T). A placement in Pyreneola , however, is contradicted by the relatively wider aperture and the absence of the characteristic incision of the columella above the adapical columellar denticle seen in all Pyreneola species. Due to its peculiar protoconch morphology, we doubt that “ Mitrella ” bittneri is a true Mitrella and place the species in “ Mitrella ” in the widest sense.

Mitrella debooyi ( Maury, 1917) , from the late Miocene of the Dominican Republic, is superficially similar concerning general shape but differs in its high multispiral protoconch (own data B.L.).

Palaeoenvironment. The specimens from Steinebrunn derive from shallow marine, inner neritic environments with sea grass (own data).

Distribution in Central Paratethys. Badenian (middle Miocene): Carpathian Foredeep: Korytnica ( Poland) ( Bałuk 1995); Vienna Basin: Steinebrunn ( Austria) ( Sieber 1958b), Sedlec (Porzteich) (the Czech Republic), Devínska Nová Ves ( Slovakia) ( Švagrovský 1981); Pannonian Basin: Szob ( Hungary) ( Strausz, 1966); southern Pannonian Basin: Hrvaćani-Drenik ( Bosnia and Hercegovina) ( Atanacković 1985); Dacian Basin: Opanec ( Bulgaria) (Kojumdgieva in Kojumdgieva & Strachimirov 1960); Făget Basin: Coşteiu de Sus, Lăpugiu de Sus ( Romania) ( Boettger 1902).

Genus Orthurella Sacco, 1890

Type species. Columbella elongata Bellardi, 1848 ; subsequent designation by Cossmann (1901: 245). Miocene, Italy.

Discussion. Landau et al. (2013) considered Orthurella Sacco, 1890 and Macrurella Sacco, 1890 (in Sacco 1890b) (type species Fusus nassoides Grateloup, 1834 , early Miocene, France) to be synonyms. In contrast to the opinion of Cossmann (1901), the type species of both genera are not conspecific. Therefore, Landau et al. (2013: 193) gave Orthurella precedence over Macrurella as first revisers.

Note that Landau et al. (2013: 193) forgot to change Macrurella into Orthurella in their discussions on Orthurella nassoides ( Grateloup, 1827) , O. pronassoides (Sacco, 1890) and O. attenuata ( Beyrich, 1854) but from the context it is clear that the authors placed these species in Orthurella .

Figures

FIGURE 1. A. Map of central and south–eastern Europe, representing the area that was partly covered by the Central Paratethys Sea. The white insert corresponds to the area that is restored in the palaeogeographic map below. B. Paleogeography of the Middle Miocene Paratethys Sea 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.

FIGURE 12 A1–A2. “Mitrella” bittneri (Hoernes &Auinger, 1880), NHMW1860/0001/0129a, lectotype, Steinebrunn (Austria). B1–B2. “Mitrella” bittneri (Hoernes & Auinger, 1880), NHMW1860/0001/0129b, paralectotype, Steinebrunn (Austria). C1– C2. “Mitrella” bittneri (Hoernes & Auinger, 1880), NHMW1860/0001/0129c, paralectotype, Steinebrunn (Austria). D1–D2. Defensina bucciniformis (Hoernes & Auinger, 1880), NHMW1876/0011/0018, lectotype, Lăpugiu de Sus (Romania). E1–E2. Defensina bucciniformis (Hoernes & Auinger, 1880), NHMW1859/0045/0601, paralectotype, Lăpugiu de Sus (Romania). F. Defensina bucciniformis (Hoernes & Auinger, 1880), NHMW1854/0035/0133, paralectotype, Lăpugiu de Sus (Romania). G. Defensina bucciniformis (Hoernes & Auinger, 1880), SMF 360679, lectotype of Mitrella inquidens Boettger, 1906, Coşteiu de Sus (Romania).