A new species of extinct giant parrot has been discovered in New Zealand (where else?), making it both the world’s largest parrot and the first species of extinct giant parrot to be discovered anywhere ever.

Standing at an estimated 1 meter (3.3 feet) tall, Heracles inexpectatus stood at nearly twice the height of New Zealand’s iconic kakapo – the previously largest known, and famously fattest, parrot.

Named after the Greek hero Heracles for its size and strength (Hercules is the name the Romans adopted in their retelling) and its unexpected discovery, the researchers say H. inexpectatus had a giant beak that could crack open almost anything it fancied. It also came in at a hefty 7 kilograms (15 pounds), about the weight of a bowling ball. Kakapos, for comparison, weigh at most 4 kilograms (9 pounds).

Heracles has been dated to around 19 million years old, found in St Bathans in Central Otago, an area in New Zealand well known for its Miocene fossil birds and animals.

As an island nation, New Zealand is no stranger to extinct giant birds – once upon a time, it housed nine species of moa, the largest of which stood at 3.6 meters (12 feet), and a penguin taller than a human. Islands often create evolutionary novelties in the form of large, usually flightless birds; other examples include the dodo of Mauritius, the elephant birds of Madagascar, the giant pigeon solitaire of Rodrigues Island, and the giant ducks of Australia.

However, no one has ever found a species of giant parrot before.  

"New Zealand is well known for its giant birds," Trevor Worthy of Flinders University said in a statement. "Not only moa dominated avifaunas, but giant geese and adzebills shared the forest floor, while a giant eagle ruled the skies.

"But until now, no one has ever found an extinct giant parrot – anywhere."

Describing it in a paper published in Biology Letters, the researchers say this fossil not only represents a new genus, but reveals another striking example of evolutionary island giantism in birds.

Like the kakapo, it was a member of the ancient New Zealand primitive flightless group of parrots very different from today’s macaws and cockatoos. Also, like the kakapo, it would have fed upon the forest ground, although unlike the kakapo, there is a possibility its huge beak gave it the advantage of eating pretty much anything it came across.

"Heracles, as the largest parrot ever, no doubt with a massive parrot beak that could crack wide open anything it fancied, may well have dined on more than conventional parrot foods, perhaps even other parrots," said Professor Mike Archer from the University of South Wales.

"Its rarity in the [fossil] deposit is something we might expect if it was feeding higher up in the food chain," he added, as parrots "in general are very resourceful birds in terms of culinary interests."

Excavations have been going on at the St Bathans site for 20 years, providing a fascinating insight into the diverse terrestrial fauna that lived in subtropical climates like New Zealand millions of years ago, very few of which have survived into modern times.