23 February 2016
Fighting Over Effigia
The debate over the placement of Effigia is at most a smoldering pile of ash and not a blazing inferno a decade after the announcement of the archosaur. The discussion included a pair of papers that discussed the anatomy of Effigia in the two assumed contexts of its placement. Sterling Nesbitt in January 2007 asserted that Effigia was in fact an early suchian precursor and possessed crocodylian anatomical features that have continued through the line into extant crocodylians. These include femoral orientation, manus proportions, and the shape and articulations of the astragalus. Sometime during 2007 the New Mexico Museum of Natural History and Science released a bulletin containing a Spencer Lucas article. Lucas, et al. 2007 asserted that Effigia's diagnostic characteristics were not more characteristic of suchian ancestors than they were of theropod ancestors. To that end, Lucas, et al. placed Effigia within the genus Shuvosaurus.