A study of the sharks and rays from the Lillebælt Clay (Early–Middle Eocene) of Denmark, and their palaeoecology

Abstract

Elasmobranch assemblages from the Eocene Lillebælt Clay Formation (Late Ypresian to Middle Lutetian) at Trelde Næs in Denmark yielded teeth of 31 different genera/species from surface collecting as well as from bulk sampling. The fauna is dominated by lamniform pelagic sharks and deepwater genera like Hexanchiformes, Centrophorus, Isistius, Echinorhinus and Pristiophorus. Coupatezia miretrainensis, Centrophorus aff. granulosus and Chlamydoselachus cf. fiedleri are reported for the first time from the Ypresian. The record of Coupatezia miretrainensis extends its stratigraphic record from the Lutetian back to the Late Ypresian, whereas the record of Centrophorus aff. granulosus extends the origin of the Centrophorus granulosus group back to the Late Ypresian from its hitherto known origin in the Lutetian. The possible presence of the sparsely known Bartonian genus Turania awaits further sampling to be confirmed. The Ichthyofauna suggests deposition in a deep-water environment in subtropical to temperate waters on the middle or outer continental shelf and upper slope at water depth down to 350 m. This is in agreement with depositional depths inferred from fossil molluscs and fish otoliths from Trelde Næs.