About the systematic status of an old and forgotten specimen of terror bird (Phorusrhacidae: Mesembriornithinae) from the Miocene of Northwestern Argentina

NORIEGA, J.I.; VEZZOSI, R.I.

La evolución de las Aves: Contribuciones del Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"

Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"

Lugar: Buenos Aires; Año: 2018; p. 69 - 77

A new record of a mid-large sized terror bird from northwestern Argentina is reported based on associated and fragmentary limb elements of a single specimen. The latter belongs to old collections of the MUFYCA (Ex-instituto de Fisiografía y Geología) of Rosario city, Argentina, which had remained unstudied since its finding during the Forties. The specimen comes from Yocavil valley at east of Loma Rica locality near Andalhuala (Catamarca Province, Argentina), from the ?Araucanense medio? levels. The bearing fossil horizon can be correlated with lower levels of the Andalhuala Formation, i.e., sediments of late Miocene age (Huayquerian SALMA or Tortonian Global Stage/Age). The preserved fossil material includes the distal end of a right femur, the proximal and distal end of a right tarsometatarsus and several fragments of shaft of the limbs. The comparison of anatomical characters and morphometric analysis allowed assigning the specimen to Mesembriornis Moreno, 1889 by showing a triangular asymmetric hypotarsus and a distally widened third tarsometatarsal trochlea. Both diagnostic morphologies define the clade Mesembriornithinae within the family Phorusrhacidae. It is noteworthy that some dimensions of the specimen presented herein exceed those known for some mesembriornithines, being very close to analogue measures in patagornithine taxa