Barroisiceras

Barroisiceras Temporal range: Coniacian^[1] PreЄ Є O S D C P T J K Pg N ↓
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Cephalopoda
Subclass:	†Ammonoidea
Order:	†Ammonitida
Family:	†Collignoniceratidae
Subfamily:	†Barroisiceratinae
Genus:	†Barroisiceras de Grossouvre, 1894
Subgenera ^[2]
B. (Alstadenites) B. (Barroisiceras) B. (Texasia)

Barroisiceras is an acanthoceratacean ammonite from the Upper Cretaceous, Coniacian,^[1] 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 (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.

Distribution

Cretaceous of Austria, Czechoslovakia, France, Hungary, Italy, Japan, Morocco, Slovakia, Spain, Trinidad and Tobago and USSR ^[2]

References

Notes

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

Bibliography

Arkell et al., 1957. Mesozoic Ammonoidea Treatise on Invertebrate Paleontology part L, Ammonoidea.

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