Rineceras sp. 2

Fig. 4B

Material examined

MOROCCO • 1 specimen; Anti-Atlas, region south-west of Rissani; basal Mougoui Ayoun Formation; Karaoui Coll.; PIMUZ 39510 .

Description

Specimen PIMUZ 39510 is mostly an internal mould (Fig. 4B), which has a conch diameter of 42.5 mm and is 14 mm wide with an umbilicus 20.5 mm wide (uw/dm ~ 0.40). The body chamber and last three chambers are partly embedded in a sideritic nodule. It has a depressed rounded-triangular whorl profile with flattened venter. Flanks and venter bear longitudinal equidistant ridges (5 on the umbilical wall, 3 to 4 on the flank and 2 between the ventrolateral ridges); a granulation is visible at some places at the crossing points of spiral ridges and growth lines.