Barroisiceras


Barroisiceras is an acanthoceratacean ammonite from the Upper Cretaceous, Coniacian, included in the family Collignoniceratidae.

Diagnosis

The shell of Barroisiceras is rather involute, coiled such that the outer whorl embraces much of the previous, and is generally compressed. Whorls are high with a strong crenulate keel and sparse umbilical tubercles that develop into pairs of commonly flat ribs.

Taxonomy

Barroisiceras is divided two subgenera, Barroisiceras and Barroisiceras ,with Alstadenites sometimes added as a third, Barroisiceras .
B. is moderately involute and the suture is rather simple. B. is more evolute and has a distinctly eccentric umbilicus and more complex suture.

Distribution

Cretaceous of Austria, Czechoslovakia, France, Hungary, Italy, Japan, Morocco, Slovakia, Spain, Trinidad and Tobago and USSR