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jacobi traditionally has been regarded an index fossil defining the base of the Cretaceous, however since 2016 this had been replaced by the first occurrence of Calpionella alpina.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.
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.Paleobiology Database - Berriasella at Fossilworks.org
Distribution Fossils of Berriasella have been found in: Jurassic Latady and Himalia Ridge Formations, Antarctica Los Molles Formation, Argentina Guasasa Formation, Cuba Chia Gara Formation, Iraq Muktinath, Nepal Punta Moreno Formation, Peru Hajar Formation, Yemen
Cretaceous President Beaches Formation, Antarctica Guchuochun Formation, China Buenavista Breccia, Colombia Stramberk Formation, Czech Republic France Szentivánhegy Limestone, Hungary Giumal Sandstone, India Shal Formation, Iran Chia Gara Formation, Iraq Carbonera and Taraises Formations, Mexico Pieniny Limestone and Rogozno Formation, Poland Chigan Formation, Russia Tollo and Miravetes Formations, Spain Dvuyakornaya Formation, Ukraine Hajar Formation, Yemen Lo valdes Formation, Chile
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