The St Bathans giant parrot was described from two bones, possibly from the same individual, recovered from 19-16 million-year-old (Early Miocene) lake-bed deposits on Home Hills Station, East of the Manuherikia River, St Bathans, central Otago.

The holotype (NMNZ S.051083, a 161 mm-long partial left tibiotarsus) and paratype (NMNZ S.051080) are held at Museum of New Zealand Te Papa Tongarewa.

The St Bathans giant parrot was very much larger than the kakapo, which is perhaps the closest relative of the fossil. Its estimated body mass was about 7 kg, more than twice that of kakapo, the world’s heaviest living parrot. Given its size and the robust nature of the bone, this giant parrot was inferred to be flightless. The kakapo is the only other flightless parrot known.

The genus is named after the Greek Heracles, who in Latin was known as Hercules, and who killed Neleus and his sons, except for Nestor. The name alludes to the fossil parrot genus Nelepsittacus (named after Neleus), members of which were also part of the St Bathans Fauna, and the extant Nestor (kaka and kea). The specific name documents the unexpected nature of this discovery.

The New Zealand strigopoid parrots (kakapo, kaka and kea) are the sister group to all other parrots globally. They are one of New Zealand’s truly archaic faunal groups, originating before the Australian parrot radiation. Heracles inexpectatus, the three species of Nelepsittacus and another kea-sized unnamed fossil attest to a diversity of parrots in this group in New Zealand in the early Miocene.

References

Worthy, T.H.; Hand, S.J.; Archer, M.; Scofield, R.P.; De Pietri, V.L. 2019. Evidence for a giant parrot from the early Miocene of New Zealand. Biology Letters 15: 20190467.

Recommended citation

Worthy, T.H. 2021. St Bathans giant parrot. In Miskelly, C.M. (ed.) New Zealand Birds Online. www.nzbirdsonline.org.nz