Onoba gianninii (Nordsieck, 1974)
Tyrrhenian Sea. Detritus feeder in the continental shelf and deeper. Original taxon: Setia (Crisillosetia) gianninii. It is the less elongate member of the genus in Mediterranean.
 
Shell « pale, semi-transparent; 5 very convex whorls, the first (protoconch) attenuated. Suture deep. About 30/40 spiral streaks on the last whorl, 15 on the penultimate. Thin umbilical fold. Comparing this undoubtedly new species with all the others of the subgenus (cf. plate R IV of Vol. III) one realizes that it does not exist any other species approachable to it is for the convexity of the whorls, the number of spirals and the shell measurements. » – F. Nordsieck: “Molluschi dei fondali della platea continentale fra la Corsica e la Sardegna”, La Conchiglia vol. 61, p.475.

350m deep, Isola Gorgona, Acipelago Toscano, W. Italy. 1,8mm. Original pictures provided by A. Nappo (IT).
(CC BY-NC-SA)

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