The Changhsingian (Late Permian) ammonoids from Baghuk Mountain (Central Iran) Author Korn, Dieter 286CA4F3-7EBC-4AEF-A66A-B2508D001367 Museum für Naturkunde, Leibniz Institut for Research on Evolution and Biodiversity, Invalidenstrasse 43, 10115 Berlin, Germany. dieter.korn@mfn.berlin Author Hairapetian, Vachik 1AB10F8F-4576-481B-9270-5DCD25110DBB Department of Geology, Esfahan (Khorasgan) Branch, Islamic Azad University, Esfahan, Iran. vhairap@gmail.com Author Ghaderi, Abbas 925F2B42-7326-4461-B2A6-83CB83ECCC63 Department of Geology, Faculty of Science, Ferdowsi University of Mashhad, Azadi Square, 9177948974, Mashhad, Iran. aghaderi@um.ac.ir Author Leda, Lucyna 81481AFA-C8EE-4E90-A954-FD0E7987621E Museum für Naturkunde, Leibniz Institut for Research on Evolution and Biodiversity, Invalidenstrasse 43, 10115 Berlin, Germany. lucyna.skorpion3@wp.pl Author Schobben, Martin 44C2A45A-B16C-434F-8F22-FC9C0FCA2551 Utrecht University, Department of Earth Sciences, Princetonlaan 8 A, 3584 CB Utrecht, The Netherlands. & Department of Geology, Esfahan (Khorasgan) Branch, Islamic Azad University, Esfahan, Iran. schobbenmartin@gmail.com Author Akbari, Amir 3C9DB6F9-2034-418F-876C-49359D07D29F Department of Geology, Esfahan (Khorasgan) Branch, Islamic Azad University, Esfahan, Iran amakbari80@yahoo.com text European Journal of Taxonomy 2021 2021-10-27 776 1 106 journal article 3782 10.5852/ejt.2021.776.1559 453c885c-f427-4a38-ab97-dc14b686e126 2118-9773 5604715 226B6C59-8620-4A29-9BEF-359BE67A1A2C Dzhulfites spinosus Shevyrev, 1965 Fig. 22 ; Table 7 Dzhulfites spinosus Shevyrev, 1965: 173 , pl. 21 fig. 9, pl. 22 fig. 1. Dzhulfites spinosus – Shevyrev 1968: 88 , pl. 2 figs 3–4. — Korn et al. 2019: 51, text-figs 20–21. Diagnosis Species of Dzhulfites with conch reaching 90 mm dm. Subadult stage with weakly trapezoidal, moderately depressed whorl profile (ww/wh =1.50–1.60) and broadly rounded venter; 6–8 coarse conical nodes on midflank per volution. Prongs of external lobe simple to trifid; altogether 14–18 notches of E, A and L lobes. Type material Holotype AZERBAIJAN • Nakhichevan Province , Dorasham 2 section ; Late Permian ; illustrated by Shevyrev (1965 : pl. 21 fig. 9); PIN 1478/60 . Material examined IRAN • 1 specimen ; Esfahan Province , Baghuk Mountain 1 section ; Hambast Formation ; MB.C.29738 • 1 specimen ; Esfahan Province , Baghuk Mountain A section ; Hambast Formation ; MB.C.29739 • 1 specimen ; Esfahan Province , Baghuk Mountain B section ; Hambast Formation ; MB.C.29740 • 2 specimens ; Esfahan Province , Baghuk Mountain E section ; Hambast Formation ; MB.C.29741 to MB.C.29742 • 1 specimen ; Esfahan Province , Baghuk Mountain G section ; Hambast Formation ; MB.C.29743 • 2 specimens ; Esfahan Province , Baghuk Mountain G section ; Hambast Formation ; MB.C.29744 to MB.C.29745 . Description Specimen MB.C.29739 has a conch diameter of 47 mm , but the beginning of the terminal body chamber is already at 31 mm , as indicated by two narrowly spaced septa ( Fig. 22B ). The weakly corroded specimen shows a ww/wh ratio of 1.50 at 32 mm dm; the whorl profile is trapezoidal with broadly rounded venter. The sculpture possesses six as well as eight conical midflank nodes on the last two volutions of the phragmocone, respectively. The suture line of specimen MB.C.29739 has an external lobe that is almost as deep as the adventive lobe; it possesses three small notches. There follow an inverted U-shaped ventrolateral saddle and an adventive lobe that is widest at its base. It has about eight small notches. The parallel-sided lateral saddle is lower than the ventrolateral saddle and the lateral lobe, subdivided by seven very small notches, is only half as deep as the adventive lobe ( Fig. 22F ). Specimen MB.C.29743 is a specimen with 48 mm conch diameter and has a phragmocone diameter of 36 mm ( Fig. 22C ). Its body chamber has a rounded-trapezoidal, weakly depressed whorl profile (ww/ wh= 1.30) with broadly rounded venter. In the subadult stage, the ww/wh ratio is higher than 1.50 and the whorl profile has a depressed oval shape. The sculpture in the subadult stage has eight coarse and pointed conical midflank nodes per volution; these nodes become much weaker on the body chamber and are replaced by weak, radial ribs, which are coarsest in the ventrolateral region. The suture line of specimen MB.C.29743 differs from the preceding in the simple, unsubdivided prongs of the external lobe that is not as deep as the adventive lobe, the inflated ventrolateral saddle and the wider lateral saddle ( Fig. 22E ). Fig. 22. Dzhulfites spinosus Shevyrev, 1965 . A–D . Lateral and dorsal views. A . Specimen MB.C.29741, section E, float. B . Specimen MB.C.29739, float. C . Specimen MB.C.29743, section G, float. D . Specimen MB.C.29744, section H, -5.40 m. E–G . Suture lines. E . Specimen MB.C.29743, at 32.5 mm dm, 16.5 mm ww, 10.5 mm wh. F . Holotype. MB.C.29739, at 32.0 mm dm, 16.0 mm ww, 10.0 mm wh. G . Specimen MB.C.29744, at 29.5 mm dm, 16.5 mm ww, 9.7 mm wh. H . Whorl profile proportions. Abbreviations: see Material and methods. Scale bar units =1 mm. Table 7. Conch dimensions (partly estimated) and ratios of selected specimens of Dzhulfites spinosus Shevyrev, 1965 from Baghuk Mountain.

Specimen	dm	ww	wh	uw	ah	ww/dm	ww/wh	uw/dm	WER	IZR
MB.C.29743	51.4	22.5	17.8	21.7	15.8	0.44	1.26	0.42	2.08	0.11
MB.C.29741	48.0	18.9	15.6	21.2	14.8	0.39	1.21	0.44	2.09	0.05
MB.C.29739	45.8	19.9	15.5	20.0	14.5	0.43	1.28	0.44	2.14	0.06
MB.C.29744	31.6	15.8	10.8	13.2	–	0.50	1.46	0.42	–	–

The suture line of the smaller specimen MB.C.29744 is remarkable because of its asymmetric external lobe with one prong being unsubdivided and the other possessing three small notches. It shows a narrow, dorsally inclined and weakly inflated ventrolateral saddle and a multiply serrated, asymmetric adventive lobe that is widest at its base ( Fig. 22G ). Remarks Dzhulfites spinosus differs most of the other species of Dzhulfites in the shape of the venter, which is broadly rounded in the new species but more or less flattened in D. nodosus and D. zalensis . Dzhulfites hebes is a very similar species in conch proportions and sculpture, but differs in the coarser, blunt nodes of the sculpture. Paratirolites kittli is a species with similar conch morphology, but possesses a deep external lobe, which is much shorter in D. spinosus . Stratigraphic range Upper part of the Hambast Formation; 7.00 to 4.70 m below the extinction horizon ( Dzhulfites spinosus Zone to Shevyrevites shevyrevi Zone ).