Leioceras opalinum ( Reinecke, 1818 )

Seyed-Emami, Kazem, Fürsich, Franz T., Wilmsen, Markus, Majidifard, Mahmoud R. & Shekarifard, Ali, 2008, Lower and Middle Jurassic ammonoids of the Shemshak Group in Alborz, Iran and their palaeobiogeographical and biostratigraphical importance, Acta Palaeontologica Polonica 53 (2), pp. 237-260 : 252-254

Leioceras opalinum ( Reinecke, 1818)

Fig. 6C.

1818 Nautilus opalinum ; Reinecke 1818: 55, pl. 1: 1, 2.

1967 Leioceras opalinum (Reinecke) 1818 ; Seyed−Emami 1967: 48, pl. 1: 12; pl. 7: 3a, b.

1987 Leioceras opalinum (Reinecke), 1818 ; Goy and Ureta 1987: 216, pl. 1: 1–13; text−figs. 2, 3 (with synonymy).

2001 Leioceras (Leioceras) opalinum (Reinecke) ; Rulleau et al. 2001: pl. 20: 4.

2004 Leioceras opalinum ( Reinecke, 1818) ; Myczyński 2004: 73, figs. 26/8, 27/5.

Material.—A small specimen from Kuhe Bashm (050511− 7/10).

Description.—Involute Leioceratinae with high−ovate to lanceolate whorl cross−section and a sharp keel. Umbilical border is rather sharp, with an indistinct peri−umbilical depression. Ornamentation consists of fine and sinuous striae.

Stratigraphic and geographic range.—Kuhe Bashm, level VII. Together with Bredyia from the Early Aalenian, Leioceras opalinum Zone , Leioceras opalinum Subzone.