A reassessment of Kelmayisaurus petrolicus, a large theropod dinosaur from the Early Cretaceous of China

Journal article

The Early Cretaceous fossil record of large-bodied theropods from Asia is poor, hindering comparison of Asian predatory dinosaur faunas with those from other continents. One of the few large Asian theropod specimens from this interval is a partial skull (maxilla and dentary) from the Lianmugin Formation (?Valanginian-Albian), the holotype of Kelmayisaurus petrolicus. Most authors have either considered this specimen as an indeterminate basal tetanuran or a nomen dubium. We redescribe K. petrolicus and note that it possesses a single autapomorphy (a deep accessory groove on the lateral surface of the anterior dentary), as well as a unique combination of characters that differentiates it from other theropods, affirming its validity. A phylogenetic analysis recovers K. petrolicus as a basal carcharodontosaurid, which is supported by various features: very deep interdental plates (a carcharodontosaurid synapomorphy), fused interdental plates (present in carchardontosaurids and a limited number of other theropods), and the absence of diagnostic features of other clades of large-bodied theropods such as abelisaurids, megalosauroids, and coelurosaurs. As such, Kelmayisaurus is the second known carcharodontosaurid from Asia, and further evidence that this clade represented a global radiation of large-bodied predators during the Earlymid Cretaceous.

Authors: Brusatte, S; Benson, R; Xu, X

• Journal: Acta Palaeontologica Polonica
• Volume: 57
• Issue: 1
• Pages: 65-72
• Publication date: 2012-03-01
• DOI: 10.4202/app.2010.0125
• EISSN: 1732-2421
• ISSN: 0567-7920
• Language: English
• Keywords: Cretaceous; Dinosauria; Theropoda; Carcharodontosauridae; China; anatomy