Berriasella

Berriasella
Temporal range: Tithonian-Berriasian
~150–145 Ma[1]
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Fossil shell of Berriasella jabronensis from Gard (France), on display at Galerie de paléontologie et d'anatomie comparée in Paris
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Subclass: †Ammonoidea
Order: †Ammonitida
Family: †Neocomitidae
Subfamily: †Berriasellinae
Genus: †Berriasella
Uhlig, 1905
Species
  • B. berthei Toucas 1890
  • B. calisto d'Orbigny 1850
  • B. callisto d'Orbigny 1847
  • B. carpathica Mazenot 1939
  • B. colombiana Haas 1960
  • B. jacobi Mazenot 1939
  • B. oppeli Kilian 1889
  • B. picteti Killian 1910
  • B. sabatasi Le Hegarat 1973
  • B. subprivasensis Krantz 1928
  • B. zacatecana Imlay 1939

Berriasella is a discoidal evolute perisphinctacean ammonite, and type genus for the neocomitid subfamily Berriasellinae. Its ribbing is distinct, consisting of both simple and bifurcated ribs that extend from the umbilical seam across the venter; its whorl section generally compressed, the venter more or less narrowly rounded. The species Berriasella jacobi traditionally has been regarded an index fossil defining the base of the Cretaceous, however since 2016 this had been replaced by the first occurrence of Calpionella alpina. Some authors regard B. jacobi as instead belonging to the genus Strambergella.[2]

Berriasella, named by Uhlig, 1905, is known from the late Upper Jurassic, Tithonian, to the early Lower Cretaceous, Berriasian and has a fairly worldwide distribution.[3]

  1. ^ Sepkoski, Jack (2002). "A compendium of fossil marine animal genera (Cephalopoda entry)". Bulletins of American Paleontology. 363: 1–560. Archived from the original on 2016-02-25. Retrieved 2017-10-18.
  2. ^ Frau, Camille; Bulot, Luc G.; Reháková, Daniela; Wimbledon, William A.P.; Ifrim, Christina (November 2016). "Revision of the ammonite index species Berriasella jacobi Mazenot, 1939 and its consequences for the biostratigraphy of the Berriasian Stage". Cretaceous Research. 66: 94–114. Bibcode:2016CrRes..66...94F. doi:10.1016/j.cretres.2016.05.007.
  3. ^ Paleobiology Database - Berriasella at Fossilworks.org