Azarinautilus Korn & Ghaderi, 2025, gen. nov.

Genus Azarinautilus gen. nov. urn:lsid:zoobank.org:act: CD71EEC0-54D7-47EC-A234-F505CEDED059 New genus B – Korn 2025: 43. Type species Azarinautilus nahidae gen. et sp. nov. Diagnosis Genus of the new family Korn & Hairapetian (in press) with a rather small, subinvolute or subevolute conch; whorl profile lyriform, venter moderately to deeply concave and bordered by raised keels, umbilical margin broadly rounded or subangular. Sculpture with conical nodes or shallow ribs in the midflank area. Suture line with narrow, rounded external lobe and broadly rounded lateral lobe. Etymology Combination of the name of the type region in East Azerbaijan and Nautilus. Included species NW Iran (this paper): Azarinautilus nahidae gen. et sp. nov., Wuchiapingian. Central Iran (Korn & Hairapetian in press): new species D to be described by Korn & Hairapetian (in press), Changhsingian. Remarks The new genus has an isolated position within the new family to be described by Korn & Hairapetian (in press) because of its conch shape and sculpture. A comparably distinctly concave venter has apparently not been described from any other genus of the family; however, species of Fididomatoceras gen. nov. show a flat or slightly concave venter bordered laterally by low ridges. Azarinautilus gen. nov. differs from the other genera of the new family to be described by Korn & Hairapetian (in press) in the size of the conchs. Specimens of Azarinautilus may reach a conch diameter of about 50 mm, while species of the other genera reach 100 mm or more. Another difference lies in the sculpture of the conchs: Azarinautilus possesses lateral ribs, which are absent in most other species of the family.