Evidence from the quadrate morphology in the American specimens of Presbyornis proved inconsistent with the hypothesis of close relationships of this anseriform genus to modern ducks and geese, but some character states remained uncertain. Here I describe in detail two fairly well preserved Presbyornis quadrates from Central Asia, which provide new evidence for the plesiomorphic, galliform-like morphology of this bone among the anseriforms. Most important, and contrary to a recent report, there is no caudomedial foramen that is present in the extant anseriforms. The only pneumatic foramen is in the basiorbital position, which is plesiomorphic for the galloanserines. At least six other plesiomorphic characters of the quadrate consistently suggest that the Presbyornithidae are stem-group anseriforms.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.