Abstract
Repeated bulk sampling for over a decade in an indurated glauconitic sandy marl horizon at St. Pankraz Salzburg, Austria, has yielded a diverse assemblage of 37 elasmobranchs (sharks and rays) from the early middle Eocene (Lutetian). This elasmobranch fauna is dominated by epipelagic and mesopelagic taxa known today to preferentially inhabit the middle or outer continental shelf and upper slope, indicating that the depositional environment of the top Member of Kressenberg Formation in Austria has a more complex bathymetric history than previously thought. As these new occurrences fill a substantial gap in the sporadic fossil record of Eocene mesopelagic elasmobranchs, comparisons of this assemblage with the coeval mesopelagic faunas indicate that this northwestern Tethyan realm association shares considerable similarities with those recovered from the North Sea Basin and the northeastern Atlantic. This suggests that the faunal homogeneity observed in neritic and coastal elasmobranch communities during the warm early middle Eocene is also characterised in mesopelagic habitats.