Holotype OS-199/3 from trench I, Goa4 Subzone in lateral and ventral view

Diagnoza

Shell thick-discoidal in shape; widely open umbilicus with relatively acute edge; width of umbilicus equals 1/3 of the shell diameter; venter broad, gently rounded; sides of the shell flat and parallel; on whole surface of last whorl three straight, distinct and deep constrictions; suture line with a broad ventral lobe with imperceptibly diverged sides in apical part and low median saddle (its height about 1/3 of the length of ventral lobe); first lateral saddle well rounded but first lateral lobe narrower than ventral lobe, sharply pointed with bent sides; second lateral saddle moderately broad; nearly straight growth lines.

Porównanie

Except for the number of constrictions comparable with Beyrichoceras sp. (B. castletonense Bisat ?), from the Upper Visean of Belgium; outline of growth line and development of constrictions are analogous to ones noted in juvenile specimen B. aff. sulcatum Bisat, coming from the Goniatites crenistria Zone of the Rheinish Slate Mountains; most similar to the "castletonense group" sensu Bisat 1954; from other species of the genus from Western Europe differs in the course of growth lines, amount and development of constrictions, venter shape, umbilicus width, shape of sides of ventral lobe and of first lateral lobe as well as in its occurrence in other (higher) stratigraphic position.

Autekologia

Występowanie geograficzne

Only the type locality

Zasięg czasowy

Carboniferous; Upper Visean - Goniatites crenulatus Zone (Goα 2-4 Subzone)

Materiały muzealne

only the type material.

Literatura

Żakowa, H. 1992. Goniatites from the Upper Visean (Kielce Syncline, the Holy Cross Mts, Poland). Geological Quarterly 36 (3): 327-344.