An endemic and previously unknown species of shorebird has been identified from fossils found in Central Otago, New Zealand.
Artist’s concept of Hakawai melvillei. Image credit: Vanesa L. De Pietri et al.
The new species, Hakawai melvillei, lived approximately 17.5 million years ago (early Miocene), a time when New Zealand was covered in subtropical forests and crocodiles roamed parts of the South Island.
According to a paper published in the Journal of Systematic Palaeontology, Hakawai melvillei was a representative of a large group of birds that comprises the South American seedsnipes (Thinocoridae) and the Australian Plains-wanderer (Pedionomidae).
“We were excited to discover that the fossil shorebird was not a typical wader, but more like an ancestral Plains-wanderer, with some seedsnipe-like features,” said Dr Venesa De Pietri of Canterbury Museum, lead author of the paper.
The Plains-wanderer and seedsnipes are unusual shorebirds as they have adapted well to living on the land.
“We’re happy to have found a fossil bird that provides a key morphological link between the two groups,” Dr De Pietri said.
“The discovery of Hakawai melvillei has confirmed our thinking that the ancestors of the Plains-wanderer and seedsnipes were wading birds, like most other shorebirds.”
“It has also confirmed previous research I’ve undertaken, with colleagues, that the Plains-wanderer and seedsnipes evolved their terrestrial habits independently.”
The discovery sheds light on evolutionary processes at work when South America, Antarctica, Australia, and New Zealand were part of the southern supercontinent of Gondwana.
Type material of Hakawai melvillei. Image credit: Vanesa L. De Pietri et al.
Hakawai melvillei, the Australian Plains-wanderer and the South American seedsnipe are all thought to have originated in East Gondwana.
The new species probably became endemic to New Zealand when it drifted apart from the rest of Gondwana.
“The discovery adds to an emerging story of New Zealand’s important role in the evolution of birds in the Southern Hemisphere,” said senior author Dr Trevor Worthy of Flinders University.
“Unfortunately, like crocodiles, turtles, and some tropical birds, which once inhabited New Zealand, the lineage represented by Hakawai melvillei is long gone.”
“We’re not sure what happened, but climatic and geographic changes during that time may have been partly responsible for its demise.”
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Vanesa L. De Pietri et al. Wading a lost southern connection: Miocene fossils from New Zealand reveal a new lineage of shorebirds (Charadriiformes) linking Gondwanan avifaunas. Journal of Systematic Palaeontology, published online October 13, 2015; doi: 10.1080/14772019.2015.1087064
