The evolutionary origin of the durophagous pelagic stingray ecomorph

Author(s)
Giuseppe Marramà, Eduardo Villalobos Segura, Roberto Zorzin, Jürgen Kriwet, Giorgio Carnevale
Abstract

Studies of the origin of evolutionary novelties (novel traits, feeding modes, behaviours, ecological niches, etc.) have considered a number of taxa experimenting with new body plans, allowing them to occupy new habitats and exploit new trophic resources. In the marine realm, colonization of pelagic environments by marine fishes occurred recurrently through time. Stingrays (Myliobatiformes) are a diverse clade of batoid fishes commonly known to possess venomous tail stings. Current hypotheses suggest that stingrays experimented with a transition from a benthic to a pelagic / benthopelagic habitat coupled with a transition from a nondurophagous diet to extreme durophagy. However, there is no study detailing macroevolutionary patterns to understand how and when habitat shift and feeding specialization arose along their evolutionary history. A new exquisitely preserved fossil stingray from the Eocene Konservat-Lagerstätte of Bolca (Italy) exhibits a unique mosaic of plesiomorphic features of the rajobenthic ecomorph, and derived traits of aquilopelagic taxa, that helps to clarify the evolutionary origin of durophagy and pelagic lifestyle in stingrays. A scenario of early evolution of the aquilopelagic ecomorph is proposed based on new data, and the possible adaptive meaning of the observed evolutionary changes is discussed. The body plan of †Dasyomyliobatis thomyorkei gen. et sp. nov. is intermediate between the rajobenthic and more derived aquilopelagic stingrays, supporting its stem phylogenetic position and the hypothesis that the aquilopelagic body plan arose in association with the evolution of durophagy and pelagic lifestyle from a benthic, softprey feeder ancestor.

Organisation(s)
Department of Palaeontology
External organisation(s)
Università degli Studi di Torino, Museo civico di Storia Naturale
Journal
Palaeontology
Volume
66
Pages
1-31
No. of pages
31
ISSN
0031-0239
DOI
https://doi.org/10.1111/pala.12669
Publication date
07-2023
Peer reviewed
Yes
Austrian Fields of Science 2012
105118 Palaeontology
Keywords
ASJC Scopus subject areas
Ecology, Evolution, Behavior and Systematics, Palaeontology
Sustainable Development Goals
SDG 14 - Life Below Water
Portal url
https://ucrisportal.univie.ac.at/en/publications/01ce543b-9bde-4eac-a0c4-b2b2c0406ced