A gargantuan reptile with a lunkhead - shaped neb and a mouthful of teeth swam the Triassic seas of southern China some 242 million year ago . According to researchers studying unexampled fossils ofAtopodentatus unicus , this crocodile - sized creature is the early bang herbivorous devil dog reptile . It used its singular snout for grazing plants underwater . The findings are publish inScience Advancesthis hebdomad .
The first fossil ofAtopodentatus unicus – or " unequalled strangely toothed " in Latin – weredescribed in 2014 . However , the skull was n’t well preserved , and at the time , researchers imagine the reptile ate by using its downturned snout to touch up invertebrates in the soft deposit , like a flamingo .
Now , a squad led by Li Chun from China ’s Institute of Vertebrate Paleontology and Paleoanthropology examine two new fossil specimens ofAtopodentatusunearthed from Middle Triassic outcrop of the Guanling Formation in Luoping County , Yunnan Province . According to their psychoanalysis , Atopodentatusdidn’t have a downturned snout . Rather , the front of the snout was form like a hammerhead . The front edges of its jaw were delineate with chisel - mold teeth , and further in , there were densely packed needle - influence teeth that formed a mesh for filter - feeding .
" To figure out how the jaw fit together and how the animal in reality feed , we bought some baby ’s clay , kind of like Play - Doh , and rebuilt it with toothpick to represent the teeth , " sketch carbon monoxide - writer Olivier Rieppel from the Field Museum of Natural History explained in astatement . Atopodentatusfed like a baleen whale , not a flamingo .
Using its chisel - like teeth , Atopodentatusscraped off pieces of alga from rock-and-roll and other subaqueous surface . Once these were loose and suspended in the water , they would be breastfeed in and then filtered by the closely packed bunches of long , thin teeth . Water goes back out , but the tooth sieve keeps works thing trapped .
These finding reveal thatAtopodentatusis the earliest marine reptile to have evolved herbivory . This evolve a 2d fourth dimension in an unrelated marine reptile calledHenodusduring the Late Triassic . This animal was an efficient sucking feeder , though it did n’t have a hammerhead . Even though a dazzling diversity of feeding stylus popped up after the end - Permian quite a little quenching 252 million years ago , no other caseful of herbivorous leatherneck reptiles have been document for the quietus of theMesozoic Era .
liveliness restoration of Atopodentatus . Y. Chen / IVPP
ikon in the text : Researchers made models out of youngster ’s clay and toothpick to see how the jaw worked . Olivier Rieppel / The Field Museum
