Stoyanowites parallelus Korn & Hairapetian & Ghaderi & Leda & Schobben & Akbari 2021, sp. nov

Stoyanowites parallelus Korn & Hairapetian sp. nov. urn:lsid:zoobank.org:act: E6C0C2D8-02EF-4E72-9E1E-78816A50573E Fig. 63; Table 37 Diagnosis Species of Stoyanowites with conch reaching 100 mm dm. Subadult stage with rectangular, compressed whorl profile (ww/wh =0.70), subangular ventrolateral shoulder and flattened venter; 10 rather coarse ventrolateral spines per half volution. Adult stage with parallel-sided, compressed whorl profile (ww/ wh= 0.60), flat venter and angular ventrolateral shoulder; 15 ventrolateral spines per half volution. Prongs of external lobe simple; altogether 13 notches of E, A and L lobes. Etymology Named after the parallel flanks of the whorl profile. Material examined Holotype IRAN • Esfahan Province, Baghuk Mountain C section; Hambast Formation, 1.70 m below the top; illustrated in Fig. 63A; MB.C.30102. Paratypes IRAN • 2 specimens; Esfahan Province, Baghuk Mountain E section; Hambast Formation; MB.C.30103 to MB.C.30104 • 1 specimen; Esfahan Province, Baghuk Mountain G section; Hambast Formation; MB.C.30105. Description Holotype MB.C.30102 is an incomplete specimen of 72 mm diameter; it allows the study of conch shape, ornament and suture line. The conch is extremely discoidal (ww/dm= 0.19) with a wide umbilicus (uw/ dm =0.47) and a compressed whorl profile (ww/wh =0.61). It has nearly parallel, slightly concave flanks, a prominent subangular ventrolateral shoulder and a weakly concave venter at the largest diameter (Fig. 63A). The sculpture is dominated by coarse ventrolateral spines, which become weaker towards the end of growth, but of which are still 15 are present on half a volution of the body chamber. They are not always connected with short ribs on the inner flank. The suture line of holotype MB.C.30102 shows the short external lobe, which has simple, weakly pouched prongs. The ventrolateral saddle is rather narrow; the adventive and lateral lobes possess six notches (Fig. 63B). Remarks Stoyanowites parallelus sp. nov. differs from S. dieneri and S. aspinosus in the flat venter and the numerous sharp ventrolateral nodes in the adult stage. Stratigraphic range Upper part of the Hambast Formation; 1.70 m below the extinction horizon (Alibashites ferdowsii Zone).