Rollandiana Kolesnikov, 1939

Harzhauser, Mathias, 2021, The Cainozoic to present-day record of Circum-Mediterranean, NE Atlantic and North Sea Cantharidinae and Trochinae (Trochoidea, Gastropoda) - a synopsis, Zootaxa 4902 (1), pp. 1-81 : 52

Genus Rollandiana Kolesnikov, 1939 †

Type species. Trochus rollandianus d’Orbigny, 1844 , OD ( Kolesnikov 1939: 701), established as section within Gibbula Risso, 1826 . Middle-late Miocene (Bessarabian), Eastern Paratethys ( Russia).

Diagnosis. Small to medium sized, depressed spherical shells with low to moderately high spire, convex whorls with faint mid-whorl angulation of last whorl. Umbilicus moderately wide and deep. Callous inner lip persisting to base of penultimate whorl. Weak or prominent spiral sculpture and prominent sigmoidal growth lines.

Remarks. Rollandiana is available according to Article 10.4 of the ICZN ( A uninominal name proposed or a genus-group division of a genus, even if proposed for a secondary (or further) subdivision, is deemed to be a subgeneric name even if the division is denoted by a term such as “section” or “division”).

The depressed shells are morphologically far from Gibbula s.s. but are somewhat reminiscent of Steromphala concerning the umbilical features and the morphology of the inner lip. The depressed-helicid outline and the convex base, however, differ clearly from the subtrigonal outline of Steromphala ..