Cochlis unica ( Bałuk, 1995 ), Harzhauser & Landau & Guzhov, 2025

Cochlis unica ( Bałuk, 1995) nov. comb.

Fig. 21A View FIGURE 21

1

–A

View FIGURE 1

4 View FIGURE 4

Polynices redempta Micht. — Csepreghy-Meznerics 1969b: pl. 5, fig. 17 [ non Pseudolinices redemptus ( Michelotti, 1847) ].

* Nacca unica sp. n. — Bałuk 1995; 195, pl. 15, fig. 9.

Nacca unica Bałuk, 1995 — Bałuk 2006: 206, pl. 3, fig. 9 [not fig. 8 = Figovina szobiensis ( Strausz, 1959) ].

Type material. Holotype, Z. PAL. U.W. No. BkK-G465 , SL: 40.0 mm, MD: 42.0 mm, Korytnica ( Poland), Figs 21A View FIGURE 21 1 –A View FIGURE 1 4 View FIGURE 4 .

Revised description. Large, globose, solid shell of 4.5 teleoconch whorls; about as high as wide ( SL /MD = 0.95). Spire conical, moderately elevated, convex, with moderately convex whorls; apical angle ~122°. Protoconch poorly preserved of ~2 smooth, convex whorls; transition into teleoconch indistinct. Suture linear, adpressed. Teleoconch whorls with weakly concave subsutural shelf, delimited by faint shoulder angulation. Last whorl slowly expanding, moderately inflated, attaining ~92% of total height. Subsutural shelf widening on last whorl with distinct concavity close to aperture. Periphery convex, below mid-whorl (~43%). Growth lines distinct and weakly prosocyrt in apical view, slightly weaker at periphery.Aperture widely D-shaped. Position of adapical tip of aperture moderately low (~79%), distinctly above mid-whorl. Aperture attaining ~71–75% of total height. Columellar lip thick, basal lip slightly expanded, outer lip broken. Columellar angle ~28°. Opercular ridge in outer lip distinct. Umbilicus moderately narrow (~13%), deep, with prominent growth lines. Parietal callus very long (~72%), strongly thickened, with weakly concave to straight margin and moderately expanding, relatively thin anterior lobe. Funicle low, insignificant, fully hidden by trigonal umbilical callus. Umbilical callus fused with anterior lobe. Narrow, concave abapical sulcus, delimited by prominent spiral swelling. Basal fasciole solid, rounded with prominent growth lines. Color pattern not preserved. Operculum unknown.

Discussion. Generic placement of this species is problematic, as the shell shape and umbilical characters would fit the genus Euspira . However, we place it in Cochlis based on its distinct opercular ridge, which is lacking in Euspira , a member of Polinicinae , which do not have a calcareous operculum, and therefore do not have an opercular ridge within the aperture. Cochlis unica ( Bałuk, 1995) is unique within the Paratethyan Naticidae due to its large and solid shell and its narrow umbilicus, which is largely covered by a thick, trigonal umbilical callus, giving it a distinctly Euspira -like profile. The holotype is a specimen with depressed spire and an adapical suture placed at the shoulder of the preceding whorls. A second specimen from Korytnica, illustrated by Bałuk (2006: pl. 3, fig. 9), documents some variability in spire height and its suture is placed below the shoulder. In summary, we place Nacca unica tentatively in the genus Cochlis based solely on the presence of an opercular ridge. We have seen no further material apart from the holotype, and therefore cannot comment if this ridge is a consistent character. Further material is required to be certain of its generic position.

Paleoenvironment. Unknown; the occurrence at Gainfarn might suggest sea-grass environments (Zuschin et al. 2007).

Distribution in Central Paratethys. Badenian (Middle Miocene): Korytnica Basin: Korytnica ( Poland). Vienna Basin: Gainfarn ( Austria) ( hoc opus). Pannonian Basin: Borsodbóta ( Hungary) ( Csepreghy-Meznerics 1969b).