title: The unexpected survival of an ancient lineage of anseriform birds into the Neogene of Australia: the youngest record of Presbyornithidae.
abstract: Presbyornithids were the dominant birds in Palaeogene lacustrine assemblages, especially in the Northern Hemisphere, but are thought to have disappeared worldwide by the mid-Eocene. Now classified within Anseriformes (screamers, ducks, swans and geese), their relationships have long been obscured by their strange wader-like skeletal morphology. Reassessment of the late Oligocene South Australian material attributed to Wilaru tedfordi, long considered to be of a stone-curlew (Burhinidae, Charadriiformes), reveals that this taxon represents the first record of a presbyornithid in Australia. We also describe the larger Wilaru prideauxi sp. nov. from the early Miocene of South Australia, showing that presbyornithids survived in Australia at least until ca 22 Ma. Unlike on other continents, where presbyornithids were replaced by aquatic crown-group anatids (ducks, swans and geese), species of Wilaru lived alongside these waterfowl in Australia. The morphology of the tarsometatarsus of these species indicates that, contrary to other presbyornithids, they were predominantly terrestrial birds, which probably contributed to their long-term survival in Australia. The morphological similarity between species of Wilaru and the Eocene South American presbyornithid Telmabates antiquus supports our hypothesis of a Gondwanan radiation during the evolutionary history of the Presbyornithidae. Teviornis gobiensis from the Late Cretaceous of Mongolia is here also reassessed and confirmed as a presbyornithid. These findings underscore the temporal continuance of Australia's vertebrates and provide a new context in which the phylogeny and evolutionary history of presbyornithids can be examined.
authors.affiliation: Canterbury Museum, Rolleston Avenue, Christchurch 8013, New Zealand; School of Biological Sciences, Flinders University, Adelaide, South Australia 5001, Australia.
authors.forename: Vanesa L
authors.identifier: 0000-0002-3786-9741
authors.initials: VL
authors.lastname: De Pietri
authors.affiliation: Canterbury Museum , Rolleston Avenue , Christchurch 8013, New Zealand.
authors.forename: R Paul
authors.identifier: 0000-0002-7510-6980
authors.initials: RP
authors.lastname: Scofield
authors.affiliation: Borissiak Paleontological Institute , Russian Academy of Sciences , Moscow, Russia.
authors.forename: Nikita
authors.initials: N
authors.lastname: Zelenkov
authors.affiliation: Australian Museum , Ornithology Section , Sydney, New South Wales, Australia.
authors.forename: Walter E
authors.initials: WE
authors.lastname: Boles
authors.affiliation: School of Biological Sciences , Flinders University , Adelaide, South Australia 5001, Australia.
authors.forename: Trevor H
authors.initials: TH
authors.lastname: Worthy
keywords: Gondwana; Miocene; Wilaru tedfordi; fossil birds; palaeobiogeography