Nebularia soliphila, Harzhauser & Landau, 2021

Harzhauser, Mathias & Landau, Bernard, 2021, The Mitridae (Gastropoda: Neogastropoda) of the Miocene Paratethys Sea, Zootaxa 4983 (3), pp. 1-72 : 46-47

Nebularia soliphila nov. sp.

figs 13A 1 –A 2, B 1 –B 2, C 1 –C 2, D 1 –D 2, E

Mitra (Nebularia) scrobiculata Brocc. — Hoernes & Auinger 1880: 80 (pars), pl. 9, figs 18–19 [non Brocchi, 1814].

Type material. Holotype: NHMW 2020 /0110/0001, SL: 56.7 mm , MD: 14.9 mm, Steinebrunn ( Austria), illustrated in Hoernes & Auinger (1880, pl. 9, fig. 18), figs 13A 1 –A 2 . Paratypes: NHMW 1864 /0001/0562, SL: 49.5 , MD: 13.7, Steinebrunn ( Austria), figs 13B 1 –B 2 ; NHMW 2020 /0110/0003, SL: 57.7 mm , MD: 14.6 mm, Steinebrunn ( Austria), figs 13C 1 –C 2 ; NHMW 2020 /0110/0002, SL: 39.7 mm , MD: 10.7 mm, Steinebrunn ( Austria), figs 13E 1 –E 2 .

Additional material. NHMW 1861 /0001/0236, SL: 39.0 mm , MD: 11.8 mm, Pöls ( Austria) , illustrated in Hoernes & Auinger (1880, pl. 9, fig. 19); figs 13D 1 –D 2; NHMW 1864 /0001/0562, 11 specimens, Steinebrunn ( Austria) ; NHMW 1997 z0178/1433, 14 specimens, Gainfarn ( Austria) .

Type locality. Steinebrunn ( Austria), Vienna Basin .

Type stratum. Silty sand of the Baden Formation.

Age. Middle Miocene, middle Badenian (Langhian).

Etymology. From Latin sol (= sun) and Greek philos (= friend); referring to the shallow sublittoral habitat.

Diagnosis. Nebularia species of moderately large size, solid, slender to moderately slender fusiform shell, with shouldered whorls, gradate spire, low aperture, and blunt spiral sculpture of broad flattish spiral cords.

Description. Shell moderately large, solid, slender to moderately slender fusiform with slightly gradate spire and deeply incised suture. Protoconch unknown. Teleoconch of nine whorls. Early teleoconch whorls weakly convex to straight sided with cancellate sculpture. Later teleoconch whorls subcylindrical with rounded shoulder. Sculpture of five to six broad, flattish spiral cords separated by narrow, shallow, weakly punctate spiral grooves. Faint secondary spiral grooves may bifurcate primary spiral cords. Last whorl subcylindrical to weakly convex, rather short, slowly contracting into short base, with moderate basal concavity. Sculpture of about 18 broad spiral cords, partly subobsolete along periphery and/or with faint secondary spiral grooves. Abapically, spiral cords narrowing over base and fasciole, spiral grooves widening. Aperture short, moderately narrow. Columellar callus narrow, thin, sharply delimited. Outer lip solid. Columella with four oblique spiral folds, decreasing in strength abapically. Fasciole prominent, twisted. Siphonal canal moderately long, wide, slightly bent to the left with deep siphonal notch.

Shell measurements and ratios. SL = 28.0– 57.5 mm, MD: 8.9–14.6 mm, AA = 26–30°, SL/MD: 3.5–3.6, AL/AW: 5.1–5.4, AH/S: 2.3–2.7.

Discussion. Pliocene Mediterranean specimens of Cancilla alligata (Defrance in Blainville, 1825), as described by Cavallo & Repetto (1992: 118, fig. 302) and Chirli (2002: 42, pl. 21, figs 3–9), are reminiscent of Nebularia soliphila nov. sp., especially in its coarse sculpture, but are smaller (SL: ~ 27 mm), have a higher last whorl, a lower spire and fewer spire whorls. Mitra cocconii Mayer-Eymar, 1898 , from the Pliocene of Prato-Ottesola ( Italy), might represent another closely related species, differing in its less incised suture, less gradate spire, slowly contracting last whorl and more delicate sculpture (see Cocconi 1873: 98, pl. 3, figs 1–2).

Hoernes & Auinger (1880) described and illustrated two specimens of this species as Mitra scrobiculata [= Cancilla praescrobiculata ( Toldo, 1889) ]. The similarity between both species, however, is superficial at best. Cancilla praescrobiculata is much more slender, lacks a shoulder and a gradate spire, has a much higher aperture and is less robust. Moreover, the occurrence of Nebularia soliphila in silty-sandy near shore settings suggests a distinct ecological separation from the deeper water Cancilla praescrobiculata . Cancilla grateloupi ( d’Orbigny, 1852) , from the Burdigalian and Langhian of the north-eastern Atlantic, is slightly reminiscent of the Paratethyan species, but differs in its much weaker shoulder and higher aperture (see Peyrot 1928: 113, pl. 9, figs 48–49).

Palaeoenvironment. Inner neritic, shallow marine environments, partly with sea grass meadows (e.g. Gainfarn, Zuschin et al. 2007; own data).

Distribution in Central Paratethys. Badenian (middle Miocene): Vienna Basin: Gainfarn, Steinebrunn ( Austria); Styrian Basin: Pöls ( Austria) (own data).