The Cenozoic age of the supposed Jurassic crab Hebertides jurassica Guinot, De Angeli & Garassino, 2007 (Crustacea, Decapoda, Brachyura)

Abstract

The specific name of the crab Hebertides jurassica Guinot, De Angeli & Garassino, 2007, reflects the belief that the single known specimen is of Jurassic age and hence would represent a very early heterotreme eubrachyuran. The specimen was collected from a quarry at Ranville in Calvados, France, where Bathonian limestones of the Calcaire de Langrune Formation outcrop. However, bryozoans in the matrix of the specimen are of undoubted Cenozoic, probably Miocene, in age. Good preservation of both crab and bryozoans in the same matrix allows the assumption that they are contemporaneous, necessitating re-dating of H. jurassica as probably Miocene in age. It seems likely that the piece of matrix was discarded in the Ranville quarry by a fossil collector who had previously visited a Cenozoic locality elsewhere. Despite the revised dating, the genus Hebertides and species H. jurassica are distinct from related Corystidae and the names can be retained.

Keywords

• Decapoda
• Jurassic
• Miocene
• Bryozoa
• France