Bistrialites

Genus of nautiloids

Bistrialites is an involute, globose Clydonautilacean belonging to the Liroceratidae with a reniform (kidney-shaped) whorl section, large funnel-shaped umbilicus, smooth surface except for spiral ornament in the region of the umbilical shoulder. Bistrialites comes from the Lower Carboniferous (Mississippian) of Europe.

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