A new rebbachisaurid sauropod from the Aptian–Albian, Lower Cretaceous Rayoso Formation, Neuquén, Argentina

Canudo Sanagustín, José Ignacio (Universidad de Zaragoza) ; Carballido, J. ; Garrido, A. ; Salgado, L.

Resumen: Rebbachisaurids are a group of basal diplodocimorph sauropods that diversified in Gondwana at the end of the Early
Cretaceous and the beginning of the Late Cretaceous. It is a group of great palaeobiogeographical interest, for it clearly
illustrates various processes of dispersal throughout Gondwana and to Laurasia prior to the breakup of Africa and South
America. However, the relationships within the group are still under discussion owing to the scarcity of cranial material
that would help clarify them. In the present paper we describe the new rebbachisaurid Lavocatisaurus agrioensis gen. et
sp. nov. from the Aptian–Albian (Lower Cretaceous) of Neuquén (Argentina). Remains have been recovered belonging
to an adult specimen (holotype) and two immature specimens (paratypes). Taken together, almost all the bones of the
taxon are represented, including most of the cranium. Lavocatisaurus agrioensis gen. et sp. nov. is the first rebbachisaurid
from Argentina with an almost complete cranium, making it possible to recognize differences with respect to
other rebbachisaurids, such as the highly derived Nigersaurus. Among its most notable characters are the presences of
a large preantorbital fenestra and maxillary teeth that are significantly larger than those of the dentary. Our phylogenetic
study places Lavocatisaurus amongst basal rebbachisaurids, as the sister lineage to Khebbashia (the clade formed by
Limaysaurinae + Rebbachisaurinae). This position, which is somewhat more derived than that previously suggested
for Comahuesaurus and Zapalasaurus (the Argentinean rebbachisaurids closest in geographical and geological terms),
reaffirms the presence of different basal rebbachisaurid lineages in the Early Cretaceous of Patagonia.

Idioma: Inglés

DOI: 10.4202/app.00524.2018

Año: 2018

Publicado en: ACTA PALAEONTOLOGICA POLONICA 63, 4 (2018), 679-691
ISSN: 0567-7920

Factor impacto JCR: 1.639 (2018)

Categ. JCR: PALEONTOLOGY rank: 17 / 56 = 0.304 (2018) - Q2 - T1

Factor impacto SCIMAGO: 0.764 - Paleontology (Q1)

Financiación: info:eu-repo/grantAgreement/ES/MINECO/CGL2017-85038-P

Tipo y forma: Artículo (Versión definitiva)

Área (Departamento): Área Paleontología (Dpto. Ciencias de la Tierra)