Cristina Pla, Ana Márquez-Aliaga, Héctor Botella
Journal of Vertebrate Paleontology 33 (4), 770-785, (1 July 2013) https://doi.org/10.1080/02724634.2013.748668
Here we present for the first time a detailed taxonomic study of a diverse chondrichthyan fauna from the Middle Triassic of the Iberian Range (Spain). The assemblage consists of isolated remains of seven species of five non-neoselachian shark genera (Palaeobates, Hybodus, Pseudodalatias, Prolatodon, gen. nov., and Lissodus), including a new species of hybodontiform shark, Hybodus bugarensis, sp. nov. In addition, a new homalodontid genus, Prolatodon, sp. nov., is erected for the taxa ‘Polyacrodus’ bucheri and ‘Polyacrodus’ contrarius. The chondrichthyans of the Iberian Range represent a heterogeneous group from a paleogeographic point of view made up of common components of Middle Triassic shark faunas of northern Europe (Hybodus plicatilis and Palaeobates angustisimus) together with species only known previously from North America and China (Prolatodon bucheri, comb. nov., and Prolatodon contrarius, comb. nov.), as well as several ‘endemic’ taxa (Pseudodalatias henarejensis, Hybodus bugarensis, sp. nov., and Lissodus aff. L. lepagei). This fauna demonstrated adaptation for a wide diversity of feeding strategies, implying that non-neoselachian sharks dominated among the predator community of Middle Triassic coastal ecosystems of Iberia. The co-occurrence with bivalves, ammonoids, and conodonts allows us to date the chondrichthyan assemblage as ‘Longobardian’ (upper Ladinian).