Description of the first complete skeleton of the extinct New Zealand goose Cnemiornis calcitrans (Aves Anatidae), and a reassessment of the relationships of Cnemiornis

The discovery of the first essentially complete Cnemiornis calcitrans skeleton is reported. This has facilitated a description of features of the skeleton not previously described and a reassessment of the phylogenetic relationships of Cnemiornis. A morphological comparison is supported by a cladistic analysis to show that Cnemiornis is the sister taxon of Cereopsis novaehollandiae. The data set based on morphological characters was insufficient to resolve the issue of whether the Cnemiornis/Cereopsis clade was the sister taxon of the rest of the Anserines or more primitive than them. The anserines (geese and swans) are the sister group to Dendrocygna, Thalassornis, and all other anatids. A 96 base pair sequence of mitochondrial DNA is reported for Cnemiornis calcitrans which shows much similarity with the equivalent section in Cereopsis, and is considerably different from other anserines. The DNA sequence supports the inclusion of the Cnemiornis/Cereopsis clade within the Anserinae.