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RESEARCH PRODUCT

Pseudodalatias henarejensisnov. sp. a new pseudodalatiid (Elasmobranchii) from the Middle Triassic of Spain

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ABSTRACT Pseudodalatiids, a chondrichthyan family of uncertain phylogenetic affinities, have been hitherto exclusively known from the tooth-based species Pseudodalatias barnstonensis (Sykes, 1971), which has a stratigraphic range restricted to the Upper Triassic of Europe. Pseudodalatias presents a characteristic dentition which allows it to hold and cut its prey, showing a neoselachian design, but lacking the triple-layered enameloid microstructure of neoselachian teeth. The discovery of Pseudodalatias henarejensis nov. sp. in the Ladinian of Spain extends the stratigraphical range and the palaeogeographical distribution of this family. This new species also demonstrates that a cutting-clutching dentition evolved progressively in the family Pseudodalatidiidae. Pseudodalatiids are likely to represent stem-batoids or stemneoselachians rather than aberrant hybodonts.