Julfanautilus Korn & Ghaderi, 2025, gen. nov.

Genus Julfanautilus gen. nov. urn:lsid:zoobank.org:act: D5ED78D7-D4E4-43D0-B9E9-193D3554B4AB new genus H – Korn 2025: 69, fig. 35. Type species Julfanautilus ashourii gen. et sp. nov. Diagnosis Genus of the family Julfanautilidae fam. nov. with thinly pachyconic, involute or subinvolute conch. Conch rapidly increasing in height with an extremely or extraordinarily high coiling rate (WER higher than 2.50). Whorls weakly embracing, whorl profile weakly depressed. Venter weakly concave, umbilical margin usually narrowly rounded, umbilical wall flat and steep. Adult ornament with extremely fine growth lines. Septa without inflexions, slightly concave. Suture line simple with shallow external lobe and broadly rounded lateral lobe. Etymology Combination of the name of the type region and Nautilus. Included species NW Iran (this paper): Julfanautilus ashourii gen. et sp. nov., Wuchiapingian; Julfanautilus hairapetiani gen. et sp. nov., Wuchiapingian. Remarks Julfanautilus gen. nov. has some similarities to Coelogasteroceras, particularly in the pachyconic conch and the shape of the venter with the shallow median groove. However, the specimens of Coelogasteroceras have a rounded umbilical margin, which differs from the angulate or subangular umbilical margin in Julfanautilus. Since the shape of the umbilical margin is very stable in numerous Carboniferous and Permian nautiloids, this is also assumed for Julfanautilus. The similarity in venter shape between Coelogasteroceras and Julfanautilus is therefore interpreted as a case of convergent morphological evolution.