Julfanautilus ashourii, Korn & Ghaderi, 2025

Korn, Dieter & Ghaderi, Abbas, 2025, Late Permian nautiloids from Julfa (NW Iran), European Journal of Taxonomy 1018, pp. 1-113 : 99-100

Julfanautilus ashourii gen. et sp. nov.

urn:lsid:zoobank.org:act:

Fig. 49 ; Table 29

New genus H, new species – Korn 2025: 70, fig. 35.

Diagnosis

Species of Julfanautilus gen. nov. with a thinly pachyconic, subinvolute conch (ww/dm ~0.65; uw/dm ~0.25), weakly depressed whorl profile (ww/wh ~1.30) and extraordinarily high coiling rate (WER ~ 3.10) at a conch diameter of 80 mm. Whorl profile with a weakly concave venter, a subangular ventrolateral shoulder, flatly convex and weakly convergent flanks, a narrowly rounded umbilical margin, a steep and flattened umbilical wall and a small imprint zone ( IZR ~0.10). Suture line with a broadly rounded and shallow external lobe and a broadly rounded lateral lobe.

Etymology

Named after Ali Reza Ashouri (Mashhad), to acknowledge his support in the project.

Type material

Holotype

IRAN – West Azerbaijan • Aras Valley; Vedioceras Beds of the Julfa Formation ( late Wuchiapingian); 2011; Korn et al. leg.; illustrated in Fig. 49 ; MB.C.32095 .

Description

Holotype MB.C.32095 is a fully chambered conch with a diameter of 87 mm ( Fig. 49A ); suggesting a total diameter of approximately 150 mm including the body chamber. It is thinly pachyconic (ww/ dm = 0.62) and subinvolute (uw/dm= 0.24) with an extraordinarily high coiling rate (WER= 3.10). There is almost no whorl overlap. The whorls are widest at the pronounced, narrowly rounded umbilical margin; the umbilical wall is steep and flattened. The flanks converge towards the pronounced ventrolateral shoulder, which separates them from the broad and weakly flattened venter. The midventer possesses a very shallow longitudinal depression. Shell remains are not preserved. The suture line has a shallow, broadly rounded external lobe and a broad and shallow lateral lobe of equal depth ( Fig. 49C ).

Remarks

Julfanautilus ashourii gen. et sp. nov. differs from J. hairapetiani gen. et sp. nov. in the open umbilicus, which is closed in J. hairapetiani and in the higher coiling rate (WER ~ 3.10 in J. ashourii but only ~ 2.60 in J. hairapetiani ).

Figures

Fig. 49. Julfanautilus ashourii gen. et sp. nov., holotype MB.C.32095 (Korn et al. 2011 Coll.) from the Vedioceras Beds of the Julfa Formation at Aras Valley. A. Lateral and apertural views. B. Reconstruction of apertural view. C. Suture line at dm =76 mm, ww =55 mm, wh =42 mm.Scale bar units =1 mm.

Tables

Table 29. Conch dimensions (in mm) and ratios of the holotype of Julfanautilus ashourii gen. et sp. nov.

Nr.	dm	ww	wh	uw	ah	ww/dm	ww/wh	uw/dm	WER	IZR
MB.C.32095	87.4	54.4	42.2	21.0	37.8	0.62	1.29	0.24	3.10	0.10