| Barroisiceras Temporal range: Coniacian 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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See text |
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Barroisiceras is an acanthoceratacean ammonite from the Upper Cretaceous, Coniacian, included in the family Collignoniceratidae.
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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 sparce 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.
Barroisiceras has been found in Europe, the Middle East, Africa, the United States, Mexico, and South America.