Baghuknautilus Korn & Hairapetian, 2025, gen. nov.

Genus Baghuknautilus gen. nov. urn:lsid:zoobank.org:act: DEB59642-18B0-46BE-ABD2-6D373AE0B857 New genus F – Korn 2025: 69. — Korn & Ghaderi 2025: 8, 98, 102–103. Type species Baghuknautilus aplomorphus gen. et sp. nov. Diagnosis Genus of the family Julfanautilidae with discoidal, involute conch. The conch rapidly increases in height with a very high to extremely high coiling rate (WER usually higher than 2.50). Whorls moderately strongly embracing, their profile ranges from compressed to weakly depressed. Adult ornament with extremely fine growth lines. Septa without inflexions, slightly concave. Suture line simple, nearly straight to straight with a low external saddle, broadly rounded internal lobe. The siphuncle has a dorsocentral position. Etymology Named after the type locality of the type species. Included species Central Iran (this paper): Baghuknautilus aplomorphus gen. et sp. nov., Wuchiapingian. Remarks In terms of conch morphology, Baghuknautilus gen. nov. shows some similarities to the genera Julfanautilus and Shahrezanautilus gen. nov. This is particularly true for the shape of the whorl profile with slightly flattened, converging flanks and the slightly flattened umbilical wall. However, the other two genera show a much higher coiling rate (WER above 3.00) than Baghuknautilus (WER around 2.50) and a much more pronounced subangular to angular umbilical margin. Baghuknautilus gen. nov. also has similarity to the Triassic genus Paranautilus (Kummel 1953; Sobolev 1989), but this differs in the more dorsal position of the siphuncle and the presence of an annular process. In addition, most species of Paranautilus have a convex umbilical wall.