The tiny mammals were among the strangest whales. If they are alive today, they would be as iconically Australian as kangaroos. In a new article published this week in the Linnean Society Zoological JournalPaleontologists have described a new species of mammalodontide – named Janjucetus DULARDI – a 25 million -year -old specimen found in Victoria, Australia.
Janjucetus DULARDI The calf and the mother swim across Victoria’s shallow seas, 25 million years ago. Image credit: Ruairidh Duncan.
“Today, some of the most emblematic whale species, such as the blue and humping whales, are the whales in Valeen,” said the paleontologist at Monash Ruaridh Duncan and his colleagues.
“These ocean giants use hair -shaped structures in their mouths, called Baleen, to filter the plankton – their main source of food.”
“On the other hand, the mammals were small (no more than 3 m), with large eyes and had short jaws lined with teeth.”
“Despite this description, we know that the mammals were, in fact, whales in Valeen … which lacked Baleen.”
“They were like a branching of the main evolutionary branch leading to the chip giants today.”
All known mammal species lived at the end of the oligocene era, between 27 and 23 million years old.
And three species named out of four were found on Victoria’s Surf Coast, southeast of Melbourne.
“The first mammalodontide was found in 1932 and in 1939 received the name Mammalodo necklace“Said paleontologists.
“There were blunt jaw bones with a complete blood and nerve food for the muscles of the face and lips”
“Curiously, the teeth were worn out in the gums, which suggests that it was nourished by crushing prey (with an abrasive grain) of the seabed.”
“In 2006, the local naturalist Stauumn Hunder found the first fossil of a species later appointed according to him, Janjucetus Hunderi. “”
“This whale wore a robust triangular muzzle with sharp teeth and powerful jaw closing muscles.”
“Although Mammalodo necklace And Janjucetus Hunderi Discuss on an surprisingly wide range of lifestyles for mammals, details of the way and when and when they have become so different from the other whales remain troubled. »»
The fossilized remains of 25 million 25 million Janjucetus DULARDI were found on the coast at Jan JUC in Victoria in 2019 by the director of the Ross Dullard school.
“”Janjucetus DULARDI Measures about 2 m long – small enough to hold on a simple standard bed, “said the researchers.
“This makes it the smallest fossil discovery whale in Australia, and perhaps the first fossil of a juvenile whale found here.”
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Ruaidh J. Duncan and al. 2025. A mystime immature toothed of the Oligocene of Australia and ideas on the morphology, the systematic and the ontogenesis of mammalodontide (cetacea: Mysticeti). Linnean Society Zoological Journal 204 (4): ZLAF090; DOI: 10.1093 / Zoolinnean / Zlaf090
