Opis

Conch thick-discoidal to globular with whorl section involute and umbilicus very small to closed; late ontogenetic shell modifications resulted in changes of whorl section, development of an apertural constriction or shell thickening; growth lines biconvex, usually crenulated; longitudinal lirae usually stronger than growth striae, rarely without spiral ornamentation; suture-line with Y-shaped ventral lobe and acute or subacute ventrolateral saddle; tendency of trifurcation of adventitious lobe only; sutural formula of advanced forms.

Synonimy

Zasięg czasowy

Carboniferous - Permian; Serpukhovian - Wordian

Literatura

Arthaber, G.  1911. Die Trias von Albanien. Beiträge zur Paläontologie und Geologie Österreich und Ungarns 24: 169-177.