INVESTIGADORES
HERNANDEZ DEL PINO Santiago Ezequiel
congresos y reuniones científicas
Título:
An Exceptional Skull of Huayqueriana (Litopterna, Macraucheniidae) from the late Miocene of Mendoza, Argentina
Autor/es:
ANALIA M. FORASIEPI; GRABRIELA I. SCHMIDT; SANTIAGO E. HERNÁNDEZ DEL PINO; ROSS D. E. MACPHEE
Lugar:
Diamante
Reunión:
Jornada; Jornadas Argentinas de Paleontología de Vertebrados; 2015
Institución organizadora:
Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción
Resumen:
The Huayquerías Formation (late
Miocene, Huayquerian Age) is exposed in central-west Argentina
(Mendoza Province). It was the subject of
paleontological studies in the first half of the 20th century
and its interest has sporadically continued since. New systematic field work revealed
novel material, such as a complete skull (IANIGLA-PV 29) from the Río Seco de la Última Aguada,
referred to Huayqueriana cf. H. cristata (Rovereto) (Litopterna,
Macraucheniidae). IANIGLA-PV 29 shares some
non-exclusive features with H.
cristata (similar size, rostral border of
the orbit almost level with distal border of M3, convergence of maxillary bones
at the level of the P3/P4 embrasure, flat snout, very protruding orbits, round
outline of premaxillary area in palatal view, and small diastemata between I3-C
and C-P1). Other differences (lack of sagittal crest) could be
the result of an important intraspecific variation if co-specificity were demonstrated. A CT scan revealed the
presence of an orbitotemporal canal in the latero-ventral aspect of the
piriform lobe cast, below the rhinal fissure, and the V2 leaving the skull
through the sphenorbital fissure, as in all other litopterns that we have studied.
IANIGLA-PV 29 body mass was estimated to
be about 400 kg.
The phylogenetic analysis failed to satisfactory resolve the position of
IANIGLA-PV 29, which may be a consequence of intraspecific variation. When
monophyly is forced Huayqueriana is
nested among macraucheniines, as the stem taxon of a clade formed by Macrauchenia and other Pliocene and late
Miocene taxa.