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 Shevyrevites corrugatus Korn & Hairapetian sp. nov. urn:lsid:zoobank.org:act: 89B3129F-6478-4C46-9CD6-DDCD7C735BF0 Fig. 19 ; Table 4 Diagnosis Species of Shevyrevites with conch reaching 60 mm dm. Subadult stage with oval, slightly compressed whorl profile (ww/wh = 0.60–0.75) and rounded venter; multiple fine ribs. Adult stage with parallelsided, slightly compressed whorl profile (ww/wh =0.60–0.75), rounded venter and rounded ventrolateral shoulder; multiple fine riblets on the flank. Prongs of external lobe bifid; altogether 11 notches of E, A and L lobes. Etymology From the Latin ‘ corrugatus ’, meaning ‘folded’, because of the corrugate sculpture. Material examined Holotype IRAN • Esfahan Province , Baghuk Mountain A section ; Hambast Formation ; illustrated in Fig. 19B ; MB.C.29718 . Paratype IRAN • 1 specimen ; Esfahan Province , Baghuk Mountain A section ; Hambast Formation ; MB.C.29719 ; illustrated in Fig. 19A . Description Holotype MB.C.29718 has 37 mm conch diameter and shows half of a volution preserved that belongs to the terminal body chamber ( Fig. 19B ); the maximum phragmocone diameter is 27 mm . The phragmocone Table 4. Conch dimensions (partly estimated) and ratios of selected specimens of Shevyrevites corrugatus Korn & Hairapetian sp. nov. from Baghuk Mountain.

Specimen	dm	ww	wh	uw	ah	ww/dm	ww/wh	uw/dm	WER	IZR
MB.C.29719	41.1	9.3	12.8	18.2	–	0.23	0.73	0.44	–	–
MB.C.29718	36.7	7.3	11.5	15.7	10.2	0.20	0.63	0.43	1.92	0.11

shows rather densely spaced septa (18 per volution), but the last four are then strikingly crowded and indicate adulthood. The conch is extremely discoidal (ww/dm=0.20) and subevolute (uw/dm =0.43) with applanate flanks and a rounded venter. The sculpture consists of numerous densely spaced and sharp radial riblets (about 30 on half a volution in the adult stage), which on the body chamber extend with a shallow concave sinus across the flanks. The suture line of the holotype has a nearly parallel-sided, weakly pouched external lobe that is almost as deep as the adventive lobe; it has asymmetric prongs that are subdivided by two notches. The slightly asymmetric ventrolateral saddle is inverted U-shaped and followed by the asymmetric adventive lobe with five small notches, an asymmetric lateral saddle and an asymmetric lateral lobe with four notches ( Fig. 19C ). Remarks The new species differs from the other species of Shevyrevites by the much weaker sculpture, which consists of feeble riblets in contrast to the coarser ribs in S. shevyrevi and the conical nodes in S. nodosus . Stratigraphic range Upper part of the Hambast Formation; float but probably 4.80 m below the extinction horizon (red nodular limestone in the Shevyrevites shevyrevi Zone ).