Wading a lost southern connection: Miocene fossils from New Zealand reveal a new lineage of shorebirds (Charadriiformes) linking Gondwanan avifaunas

Abstract

An endemic and previously unknown lineage of shorebirds (Charadriiformes: Scolopaci) is described from early Miocene (19–16 Ma) deposits of New Zealand. Hakawai melvillei gen. et sp. nov. represents the first pre-Quaternary record of the clade in New Zealand and offers the earliest evidence of Australasian breeding for any member of the Scolopaci. Hakawai melvillei was a representative of the clade that comprises the South American seedsnipes (Thinocoridae) and the Australian Plains-wanderer (Pedionomidae), and presumed derived features of its postcranial skeleton indicate a sister taxon relationship to Australian pedionomids. Our findings reinforce that terrestrial adaptations in seedsnipes and the Plains-wanderer are convergent as previously proposed, and support an ancestral wading ecology for the clade. Although vicariance events may have contributed to the split between pedionomids and H. melvillei, the proposed sister taxon relationship between these taxa indicates that the split of this lineage from thinocorids must have occurred independently from Australia and Zealandia's separation from the rest of Gondwana.

http://zoobank.org/urn:lsid:zoobank.org:pub:FD3E50A9-EE95-4660-880A-A60B0DE2CEF4

Keywords:

• Scolopaci
• Pedionomidae
• Miocene
• fossil birds
• St Bathans Fauna

Acknowledgements

We are grateful to K. Roberts, P. Horton and G. Mayr for access to comparative material. We thank Lynx Edicions for permission to use the images in Figure 4. We are grateful to the landowners A. and E. Johnstone of Home Hills Station and J. and T. Enright, Dunstanburn Station, Southern Lakes Holdings Ltd, for access to sites, and to J. Worthy for sorting the material. We also thank G. Gully and B. Choo for their assistance with preparing figures. This work was funded by grants from the Australian Research Council DP0770660 to S. Hand et al. and DP120100486 to T. H. Worthy et al. We are thankful for comments by A. Louchart and one other, anonymous, reviewer which helped improve this manuscript.