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.
Insights into the Evolutionary History of an Extinct South American Freshwater Snail Based on Historical DNA
