Gatunek typowy
Gastrioceras modestum Boese, 1919

Opis

globular to thick-discoidal shell, more or less involute with ventral side broadly rounded; moderately evolute on inner whorls, but no extended ophioconic stage, later with moderately wide or narrow umbilicus; growth lines on young stages usually with ventral salient, at maturity with broad sinus; umbilical shoulder of immature whorls may be slightly nodose, commonly with multiple spiral threads or simple transverse lamellae; ventral lobe fairly wide, height of median saddle about or exceeding half the height of entire ventral lobe; first lateral saddle broadly rounded, adventitious lobe deep, relatively wide and bell-shaped. 

Synonimy
Eoasianites Miller et Furnish, 1940

Zasięg czasowy

Carboniferous (Serpukhovian) - Permian (Sakmarian)

Literatura

Ruzhentsev, V.E. 1936. Paleontologicheskie zametki o kamennougol'nykh i permskikh ammoneiakh.  Problemy sovetskoi geologii 12: 1072-1088.