Thursday, October 17, 2024

[Paleontology • 2024] Emiliasaura alessandrii • First Valanginian (Early Cretaceous) Ornithopod (Ornithischia: Ornithopoda) from Patagonia

  

Emiliasaura alessandrii
R.A. Coria, Cerda, Escaso, Baiano, Bellardini, Braun, L.M. Coria, Gutierrez, Pino, Windholz, Currie & Ortega, 2024 


Highlights: 
• A new taxon of the dinosaur clade Ornithopoda, Emiliasaura alessandri, is described.
Emiliasaura is the first recognized South American rhabdodontoid ornithopod taxon.
Emiliasaura represents the earliest Patagonian Cretaceous ornithischian dinosaur.

Abstract
Here we describe a new ornithopod speciesEmiliasaura alessandrii gen. et sp. nov. from Valanginian rocks (Early Cretaceous) of northwestern Patagonia. This new taxon exhibits affinities with the Rhabdodontomorpha and is primarily represented by two specimens of mid-sized ornithopods collected from different sites and stratigraphical levels of the Mulichinco Formation. The holotype specimen MLL-Pv-001 includes the coracoid, the proximal end of a scapula, a humerus and a complete right hind limb, whereas the paratype specimen MLL-Pv-006 preserves vertebral elements, haemal arches, an incomplete pelvis, and nearly complete hind limbs. The new taxon has an anteroposteriorly elongate ilium with a sigmoidal dorsal border and broad brevis shelf, a femur shaft with an extensive, proximally positioned fourth trochanter, and a second pedal digit with a short, robust, blunt ungual phalanx similar to those in Ankylopollexia ornithopods. The new ornithopod taxon formed part of a diverse dinosaur association from the Mulichinco Fm that includes dicraeosaurid sauropods and carcharodontosaurid theropods, and represents the first South American record of a rhabdodontoid, and the oldest and most primitive representative of this clade.
 


Emiliasaura alessandrii gen. et sp. nov. 


R.A. Coria, I.A. Cerda, F. Escaso, M.A. Baiano, F. Bellardini, A. Braun, L.M. Coria, J.M. Gutierrez, D. Pino, G.J. Windholz, P.J. Currie and F. Ortega. 2024. First Valanginian (Early Cretaceous) Ornithopod (Dinosauria, Ornithischia) from Patagonia. Cretaceous Research. 106027. DOI: doi.org/10.1016/j.cretres.2024.106027