An unusual new archosauriform from the Middle–Late Triassic of southern Brazil and the monophyly of Doswelliidae
Article first published online: 21 MAR 2011
© 2011 The Linnean Society of London
Zoological Journal of the Linnean Society
Volume 161, Issue 4, pages 839–871, April 2011
How to Cite
DESOJO, J. B., EZCURRA, M. D. and SCHULTZ, C. L. (2011), An unusual new archosauriform from the Middle–Late Triassic of southern Brazil and the monophyly of Doswelliidae. Zoological Journal of the Linnean Society, 161: 839–871. doi: 10.1111/j.1096-3642.2010.00655.x
- Issue published online: 21 MAR 2011
- Article first published online: 21 MAR 2011
- Received 16 July 2009; revised 3 January 2010; accepted for publication 11 January 2010
- South America;
Until now the Doswelliidae was considered a monospecific family including Doswellia kaltenbachi from the Late Triassic of North America. The phylogenetic position of this taxon remained enigmatic until recently, when a sister-group relationship with the Proterochampsidae was suggested. In the present contribution we describe the new doswelliid species Archeopelta arborensis gen. et sp. nov. from the Middle–Late Triassic of Brazil. A cladistic analysis recovered Archeopelta, Doswellia, and Tarjadia within a monophyletic group of basal archosauriforms, the Doswelliidae. The monophyly of this family is supported by the presence of osteoderm ornamentation that is coarse, incised, and composed of regular pits and the presence of an unornamented anterior articular lamina. Archeopelta is more closely related to Doswellia than to other archosauriforms by the presence of basipterygoid processes anterolaterally orientated, dorsal centra with a convex surface, width of the neural arch plus ribs of the first primordial sacral that are three times the length of the neural arch, and iliac blade laterally deflected, with strongly convex dorsal margin, and a length less than three times its height. The phylogenetic analysis indicates that Doswellidae is the closest large monophyletic entity to Archosauria, which achieved a wide palaeolatitudinal distribution during the late Middle and Late Triassic time span.
© 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 161, 839–871.