Paleontologists have discovered the fossilized remains of two new small pachycephalosaurs. Formation of dinosaur park Alberta and another province Hell Creek Formation of Montana.
Sphaerotorus Buchholzee A small species that fights beneath large pachycephalosaurs in the Hell Creek Formation of Montana, USA. Image credit: ABelov2014 / CC BY-SA 3.0 Certificate.
One of the new species of dinosaur named. Sphaerotorus rionsii lived in what is now Canada 75 million years ago.
the other one is, Sphaerotorus triregnum lived in the United States about 67 million years ago.
Both species belong to Sphaerosolos a genus of small dinosaurs of the subfamily Pachycephalosauridae within the family Pachycephalosauridae.
“Despite being poorly represented in the fossil record, including a thickened frontoparietal dome and hypothetical head-butting behavior, pachycephalosaurids are some of the most iconic dinosaurs,” lead authors Philip and Patricia・Dr. Carrie Woodruff, a paleontologist at the Frost Museum, said: Science and the Museum of the Rockies and its friends.
“While the true function of their unusual cranial domes remains debated, considerable research has focused on their ontogeny and diversity.”
“This study is complicated by the unusual fossil record, which consists mostly of unsegmented skull remains, and associated skeletons are extremely rare.”
“This pattern may be the result of small body size and taphonomic bias against delicate skeletal preservation and recovery, as well as the robust and diagnostic nature of the bones that make up the cranial dome.”
Holotype of left flat bone Sphaerotorus triregnum. Scale bar represents 1 cm. Image credit: Woodruff other., doi: 10.1002/spp2.1535.
Sphaerotorus rionsii and Sphaerotorus triregnum Each is represented by an isolated squamous epithelium the skull found in most reptiles, amphibians, and birds.
The holotype of Sphaerotorus rionsii “It was collected north of the Red Deer River in the northeastern part of Dinosaur Provincial Park, Alberta, Canada,” the researchers said.
The holotype of Sphaerotorus triregnum It was collected from the lower half of the Hell Creek Formation, approximately 45 km southwest of the town of Jordan, Garfield County, Montana, USA. ”
“The specimens were collected from the same channel complex and within 500 meters of the location of the dromaeosaur holotype.” Acheloraptor temeltyorum”
“These two new specimens are about the same size as the squamosal. Sphaerotorus Buchholzee and has several overlapping forms. Sphaerosolos Genus. ”
These new species fill a morphological gap in the pachycephalosaur fossil record and show that multisegment forms were more diverse than previously realized.
“Description of two new species of small pachycephalosaurs of the same genus Sphaerosolos “This provides further insight into the evolution of North American pachycephalosaurs,” the scientists said.
“Aspects of the phylogeny of pachycephalosaurs remain unresolved and disputed, in part due to the incomplete nature of their remains, and this analysis focuses on two small North American pachycephalosaur phylogenies. This is the first time we have identified evolutionary potential in different lineages.”
Holotype of right flat bone Sphaerotorus rionsii. Scale bar represents 1 cm. Image credit: Woodruff other., doi: 10.1002/spp2.1535.
“Sphaerotorus rionsii and Sphaerotorus triregnum Please provide the following evidence:
(i) Small-bodied dinosaur species have not yet been discovered in well-sampled geological formations.
(ii) pachycephalosaur diversity in the Dinosaur Park and Hell Creek formations is richer than previously thought, and pachycephalosaur diversity in North America is likely to continue to increase;
(iii) Species with ornaments consisting of multisegment rows are indeed more numerous and diverse throughout the Pachycephalosauridae than previously known.
(iv) North American pachycephalosaurs appear to have remained relatively diverse throughout the Maastrichtian period, which is consistent with dinosaurs throughout the latest Cretaceous period of North America up to the end-Cretaceous extinction event. Implications for understanding the dynamics of evolution and diversity. ”
of findings appear in the diary paleontology papers.
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D. Cary Woodruff other. 2023. His two new species of small pachycephalosaurs from the Upper Cretaceous of North America (Dinosauria, Aminocephala) suggest hidden diversity in well-sampled strata. Masu. Paleontology Papers 9 (6): e1535; doi: 10.1002/spp2.1535
Source: www.sci.news
