Redescription of Dawndraco kanzai Kellner, 2010 and reassignment of the type specimen to Pteranodon sternbergi Harksen, 1966

Abstract

The previous most comprehensive study on Pteranodon recognized two species of Pteranodon: P. longiceps and P. sternbergi. Complete skeletons of Pteranodon are rare, and one of the best preserved (UALVP 24238) has been identified as both P. sternbergi, and as a new genus and species, Dawndraco kanzai.  Here, the specimen is redescribed, the rostral apex is identified for the first time, new details of its provenance and preparation history are presented, and its taxonomic placement is discussed.  Whereas the shape of the rostrum appears at first glance to distinguish it from known Pteranodon, this feature is more parsimoniously interpreted in the context of sexual dimorphism; males have a longer and therefore more shallowly tapering rostrum.  Metrics from this specimen, and from published photographs and illustrations, support the conclusion that the rostrum of UALVP 24238 is neither unique, nor grounds for recognition of a taxon distinct from Pteranodon sternbergi.  Other putatively unique features of UALVP 24238 are examined and found unconvincing.