A newly identified species of ancient crocodile from Australia measured more than seven metres in length.
Long ago, a gigantic prehistoric creature known as Gunggamarandu maunala stalked the waterways of Australia’s southern eastern Queensland. Gunggamarandu was big, far bigger than any crocodylian reptile found so far in Australia.
This creature, identified by scientists from the University of Queensland, is a new species of crocodile that roamed the waters around Queensland millions of years ago.
Researchers made the identification after they examined the partial skull of a specimen that was unearthed in the Darling Downs region of Queensland during the 19th Century, but which had been overlooked for further investigation and lain undisturbed among other specimens for decades.
“This is one of the largest crocs to have ever inhabited Australia,” says Jorgo Ristevski, a PhD candidate from the University of Queensland’s School of Biological Sciences, who led the team that made the discovery.
“At the moment it’s difficult to estimate the exact overall size of Gunggamarandu since all we have is the back of the skull – but it was big.
“We estimate the skull would have been at least 80 centimetres long and based on comparisons with living crocs, this indicates a total body length of around seven metres.
“This suggests Gunggamarandu maunala was on par with the largest Indo-Pacific crocodiles – a Crocodylus porosus) – ever recorded.
“We also had the skull CT-scanned, and from that, we were able to digitally reconstruct the brain cavity, which helped us unravel additional details about its anatomy.
“The exact age of the fossil is uncertain, but it’s probably between two and five million years old.”
Gunggamarandu belonged to a group of crocodylians called tomistomines or ‘false gharials’.
“Today, there’s only one living species of tomistomine, Tomistoma schlegelii, which is restricted to the Malay Peninsula and parts of Indonesia,” says Jorgo.
“With the exception of Antarctica, Australia was the only other continent without fossil evidence of tomistomines.
“But with the discovery of Gunggamarandu we can add Australia to the ‘once inhabited by tomistomines’ list.”
Despite its discovery, the fossil skull of Gunggamarandu maunala remained a scientific mystery for more than a century.
The specimen piqued the interest of then-young graduate student Dr Steve Salisbury in the 1990s, but a formal study was not done until Jorgo and his team began their examination.
“I knew it was unusual, and potentially very significant, but I didn’t have the time to study it in any detail,” Dr Salisbury said.
“The name of the new species honours the First Nations peoples of the Darling Downs area, incorporating words from the languages of the Barunggam and Waka Waka nations.
“The genus name, Gunggamarandu, means ‘river boss’, while the species name, maunala, means ‘hole head’.
“The latter is in reference to the large, hole-like openings located on top of the animal’s skull that served as a place for muscle attachment.”
Feature image: Artistic representation of Gunggamarandu maunala
CREDIT: Eleanor Pease