Los cocodrilos alodaposúquidos del Cretácico Superior de Rumanía en el XVI Annual Meeting de la EAVP

Otro de los trabajos presentados por integrantes del Grupo de Biología Evolutiva de la UNED en el pasado XVI Annual Meeting de la European Association of Vertebrate Paleontologists (EAVP) fue la comunicación sobre el estudio sistemático de algunos ejemplares de alodaposúquidos procedentes del Maastrichtiense de Rumanía. Allodaposuchidae es un clado de crocodiliformes recientemente descrito y está integrado por formas exclusivamente europeas restringidas al Cretácico Superior. En el presente trabajo se analiza la validez de la especie Allodaposuchus precedens y la designación de un neotipo de la misma. El resumen es el siguiente:

Allodaposuchus precedens is a basal member of Eusuchia, established almost a century ago by Ferenc Nopcsa on a set of cranial and postcranial remains from the Maastrichtian of Vălioara (Romania). It was the first described member of the recently defined clade Allodaposuchidae, one of the closest outgroups to Crocodylia.

Attribution of the original material studied by Nopcsa to a single individual cannot be confirmed. Thus, subsequent papers considered only a fragmentary skull table as the lectotype of the species. This lectotype is no longer sufficient to support the diagnosis of a distinct species and it cannot be distinguished from most of the better-known allodaposuchids. Based on the type series alone, A. precedens is a nomen dubium.

A nearly complete skull from the Maastrichtian of Oarda de Jos (Romania), referred to A. precedens, could form the basis for a new species. Alternatively, given the widespread historical use of the name, nomenclatural stability might be better served by designating a neotype for A. precedens. The authors have chosen this avenue; applying to the ICZN asking to set aside all previous type fixations and designate the Oarda de Jos skull as the neotype for A. precedens. This specimen presents several autapomorphies and an exclusive combination of characters within Allodaposuchidae, allowing an emended diagnosis for A. precedens.

The neotype designation is of utmost importance for the objective identification of this species, recognized as the type species of Allodaposuchidae. This proposal is necessary for future phylogenetic analyses and assessments of the Upper Cretaceous crocodyliform diversity.