At least three novel species of theropod have been found in the Wayan Formation , Idaho . The dinosaur are other members of the family that finally led to terrorise devil such asTyrannosaurus king , although these ancestral versions were on a smaller scurf . The same exploration mission also turned up bollock from oviraptorosaurs , the so - call “ wimp from hell ” with distinctively odd skulls and grasping hired man .
Western North America has been an exceptionally fertile source of dinosaur fossils , particularlytheropods , the group of carnivorous dinosaurs that included tyrannosaurids andVelociraptors . Like neighboringWashington , Idaho has been something of an exception , but a report inHistorical Biologystarts the cognitive operation of changing this .
Montana State University Ph.D. studentL.J. Krumenackerexamined fossils from the Wayan Formation in south - eastern Idaho . “ The Wayan Formation has have fiddling paleontological attention due to a lack of solid and well - studied outcrop , ” the paper notes .
Unfortunately , Krumenacker ’s explorations turned up no about complete specimens , but the paper notes there is “ A diversity of theropod anatomy now recognized from various disjunct dentition , vertebra , eggs , and shell . ” It is the multifariousness that has drawn the writer ' attention , with a surprising number of species appear for such a minor identification number of fossils .
Tyrannosauroid and suspected tyrannosauroid tooth found in the Wayan Foundation , south - due east Idaho . Credit : Krumenacker et al
Identifying species from isolated bone or teeth , let alone eggshell , is challenging , but the paper report , “ Theropods recognized from isolated teeth include a large potential tyrannosauroid , a small tyrannosauroid , dromaeosaurids , and undetermined theropods . ”
Among the bollock is a pair from a largeoviraptorosaur , the first evidence that these feather dinosaur , the gravid known to have lived in Idaho , inhabited the sphere at this prison term .
The finds are from the Albian and Cenomanian level , just about in the middle of the Cretaceous menstruum , 113 to 94 million years ago . At this breaker point in time , the tyrannosauroids were nothing like their descendants 30 million years after . The “ large potential ” specimen referred to in the paper issuggestedby Krumenacker to probably have been about the size of a horse , while its small relative would have been equivalent to a mid - sized dog .
Unfortunately , it is unmanageable to learn much from such scattered fragments . The paper notes , “ The fragmentary specimens identify here mostly foreclose precise taxonomic identifications . ” Nevertheless , Krukenmackersaid , “ I put my dear attempt into it . It ’s possible I could discover some identifications are wrong if we find more complete remain later . But I ’d be vibrate because then we ’d have an even better apprehension . ”
Such finds may not excite the public resource like a devil the sizing ofthree buses , but for fossilist they are important . “ We do n’t really have many dinosaurs from this time menstruum , ” pronounce Krumenacker ’s supervisor ProfessorDavid J Varricchio . “This new evidence is really filling in the time , temporal and spatial break . ”
“ While these clay are true meager , their presence show that a substantial variety of theropod existed in the Albian to Cenomanian environment of southeastern Idaho , ” the newspaper publisher concludes , make the region “ Among the most diverse reported for this time period in North America . ”
