Jonoichthys challwa gen. et sp. nov., a new Aspidorhynchiform (Osteichthyes, Neopterygii, Teleosteomorpha) from the marine Upper Jurassic sediments of Argentina, with comments about paleobiogeography of Jurassic aspidorhynchids


en Comptes Rendus Palevol 14 (4) - Pages 291-304

Published on 30 June 2015

Aspidorhynchiformes as a whole are incompletely understood. Here, a new aspidorhynchiform, Jonoichthys challwa gen. et sp. nov., is described based on a single three-dimensionally preserved specimen recovered from Upper Jurassic marine rocks of the Vaca Muerta Formation, Neuquén, southern Argentina. The new taxon is based on a unique combination of characters (e.g., large skull roof plate composed by the fusion of certain bones; ‘L’-shaped preoperculum with a single main preopercular sensory canal that lacks sensory tubules; three predentary tooth rows; an accessory cusp in the teeth of the median predentary tooth row, and a robust and deep body). It is expected that the morphological information provided here could be useful to further understanding of aspidorhynchiform phylogeny and Neuquén Basin biodiversity.


Neopterygii, Aspidorhychiformes, South America, Tithonian, Gondwana, Paleobiogeography, Taxonomy

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