Alibashinautilus Korn & Ghaderi, 2025, gen. nov.

Genus Alibashinautilus gen. nov. urn:lsid:zoobank.org:act: BD4CEDE2-0145-467A-BD60- AD 2C0216959E New genus D – Korn 2025: 55. Type species Alibashinautilus vetus gen. et sp. nov. Diagnosis Genus of the family Rhiphaeoceratidae with subevolute or evolute conch; whorl profile circular or slightly compressed or depressed with broadly rounded venter and flanks. Sculpture with low, rounded radial ribs on the flanks or without ribs. Suture line with shallow external lobe and broadly rounded lateral lobe; internal lobe rather deep, without annular process. Etymology Combination of Ali Bashi and Nautilus; because of the type locality of the type species. Included species NW Iran (this paper): Alibashinautilus vetus gen. et sp. nov., Wuchiapingian; Alibashinautilus ambiguus gen. et sp. nov., Changhsingian. Remarks The new genus comprises species with a simple conch morphology. These are widely umbilicate forms with a circular or weakly compressed whorl profile and a low coiling rate. This morphology distinguishes them from the vast majority of Late Carboniferous and Permian nautilids. The simple morphology of these species makes it challenging to determine their genus and family. It is unclear whether they belong to a conservative evolutionary lineage of simple forms or if they are a result of morphological simplification from more complex forms. The placement of the new genus in the family Rhiphaeoceratidae is based on the shape and sculpture of the shell. Alibashinautilus gen. nov., like Rhiphaeoceras, has a rather simple oval, rounded whorl profile. However, the juvenile conch is not preserved in the Julfa material, so it is not known whether the first whorl is small, as in the Rhiphaeoceratidae, or large, as in the Aktubonautilidae. Therefore, the assignment of Alibashinautilus can only be made with reservations.