Diversity, palaeoecology and palaeoenvironmental significance of the Eocene chondrichthyan assemblages of the Bolca Lagerstätte, Italy

Autor(en)
Giuseppe Marramà, Giorgio Carnevale, Jürgen Kriwet
Abstrakt

Over the last few years, the morphology, taxonomy and systematics of the cartilaginous fish taxa of the two main sites of the Bolca Lagerstätte, Italy, (Pesciara and Monte Postale sites) have been extensively discussed in a series of papers, resulting in a complete revision of this neglected component of the Eocene Tethyan ichthyofauna. Here, we provide a comprehensive overview of the diversity, palaeoecology and palaeoenvironmental significance of the two chondrichthyan assemblages of the Pesciara and Monte Postale sites. The assemblages include 14 shark species (Lamniformes and Carcharhiniformes) and batoids (Torpediniformes, Rhinopristiformes, Myliobatiformes, Platyrhinidae and Zanobatidae), as well as a single putative chimaeriform. The Pesciara and Monte Postale sites are characterized by eight chondrichthyan taxa each, but the taxonomic compositions are distinctly different reflecting the dissimilarities in the overall composition of both fish assemblages. Palaeoecological interpretations and habitat preferences of the two chondrichthyan assemblages are consistent with previously hypothesized palaeoenvironmental settings based on sedimentological, palaeontological and geochemical evidence. The chondrichthyan assemblages of the two sites appear to be constituted by ecologically vicariant taxa, with both characterized by a predominance of benthic species with durophagous/cancritrophic feeding modes. Taxonomic composition, habitat preferences and palaeobathymetric analyses support the hypothesis that both assemblages occupied tropical marine shallow waters (likely up to 50 m deep) of the inner portion of the Lessini Shelf. The taxonomic composition of both sites is considerably different from that of any other contemporaneous Tethyan and Boreal
chondrichthyan assemblages.

Organisation(en)
Institut für Paläontologie
Externe Organisation(en)
Università degli Studi di Torino
Journal
Lethaia: an international journal of palaeontology and stratigraphy
Anzahl der Seiten
16
ISSN
0024-1164
DOI
https://doi.org/10.1111/let.12436
Publikationsdatum
07-2021
Peer-reviewed
Ja
ÖFOS 2012
105118 Paläontologie
Link zum Portal
https://ucris.univie.ac.at/portal/de/publications/diversity-palaeoecology-and-palaeoenvironmental-significance-of-the-eocene-chondrichthyan-assemblages-of-the-bolca-lagerstatte-italy(da27b003-4428-445c-bd55-efd8bcc0d87b).html