Barroisiceras

Barroisiceras is an acanthoceratacean ammonite from the Upper Cretaceous, Coniacian,[1] included in the family Collignoniceratidae.

Barroisiceras
Temporal range: Coniacian[1]
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Fossil of Barroisiceras species. Coniacian of Madagascar
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Subclass: †Ammonoidea
Order: †Ammonitida
Family: †Collignoniceratidae
Subfamily: †Barroisiceratinae
Genus: †Barroisiceras
de Grossouvre, 1894
Subgenera[2]
  • Barroisiceras (Alstadenites)
  • Barroisiceras (Barroisiceras)
  • Barroisiceras (Texasia)

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 (Barroisiceras) and Barroisiceras (Texasia),with Alstadenites sometimes added as a third, Barroisiceras (Alstadenites). B. (Barroiciceras) is moderately involute and the suture is rather simple. B. (Texasia) 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 [2]

References
Notes
  1. Sepkoski, Jack (2002). "Sepkoski's Online Genus Database". Retrieved 2014-05-28.
  2. "Paleobiology Database - Barroisiceras". Retrieved 2014-05-28.
Bibliography


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