Chilantaisaurus maortuensis, Hu, 1964

Rauhut, Oliver W. M., 2003, The interrelationships and evolution of basal theropod dinosaurs, Special papers in palaeontology 69, pp. 1-213 : 29

'Chilantaisaurus' maortuensis Hu, 1964

Age . Aptian/Albian.

Occurrence. Unnamed unit, Nei Mongol Zizhiqu, China.

Diagnosis. Maxilla very high underneath the antorbital fenestra; medial crest on the fused frontals; caudal vertebrae with a small, deep depression underneath the transverse process.

Remarks. 'Chilantaisaurus' maortuensis is based on an incomplete skull, an axis and several caudal vertebrae ( Hu 1964). The material comes from a different locality and slightly lower horizon than C. tashuikouensis . The two species were referred to the same genus because of similarities in the teeth and caudal vertebrae ( Hu 1964, p. 63). However, the teeth of 'C.' maortuensis do not differ significantly from teeth of other theropods, such as Afrovenator and Torvosaurus , and the teeth referred to C. tashuikouensis cannot be shown to belong to this taxon with any certainty. Three vertebrae in the collections of the IVPP bear the same specimen number (IVPP V 2884) as the holotype of C. tashuikouensis . One of them shows the same depressions underneath the transverse process as found in ‘ C.’ maortuensis' , however, this specimen is much too small to belong to the gigantic holotype of C. tashuikouensis . The two other vertebrae are the right size, but they are very unlike the vertebrae of ‘ C maortuensis , and one of them seems to represent a sauropod rather than a theropod. Furthermore, the holotype of ' C.' maortuensis represents a considerably smaller animal than that of C. tashuikouensis , although the intensive fusion of some of the skull bones (frontals, braincase) indicates that it represents an adult individual. Thus, it seems very unlikely that both species can be referred to the same genus and a new generic name for ‘ C.’ maortuensis will be proposed in a forthcoming publication by D. Chure.