Barroisiceras
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Barroisiceras Temporal range: Coniacian |
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| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Cephalopoda |
| Subclass: | †Ammonoidea |
| Order: | †Ammonitida |
| Family: | †Collignoniceratidae |
| Subfamily: | †Barroisiceratinae |
| Genus: |
†Barroisiceras de Grossouvre, 1894 |
| Subgenera | |
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Barroisiceras is an acanthoceratacean ammonite from the Upper Cretaceous, Coniacian, included in the family Collignoniceratidae.
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.
Barroisiceras is divided two subgenera, Barroisiceras (Barroisiceras) and Barroisiceras (Texasia),with Alstadenites sometimes added as a third, Barroisiceras (Alstadenites). B.(Barroiciceras) is modertely involute and the suture is rather simple. B. (Texasia) is more evolute and has a distinctly eccentric umbilicus and more complex suture.
Cretaceous of Austria, Czechoslovakia, France, Hungary, Italy, Japan, Morocco, Slovakia, Spain, Trinidad and Tobago and USSR
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