Gulosaurus Temporal range: Early Triassic, | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Reptilia |
Order: | † Grippidia |
Genus: | † Gulosaurus Cuthbertson, Russell & Anderson, 2013 |
Type species | |
†Gulosaurus helmi Cuthbertson et al., 2013 |
Gulosaurus is an extinct genus of basal grippidian ichthyopterygian known from the Early Triassic Vega-Phroso Siltstone Member of the Sulphur Mountain Formation of east-central British Columbia, Canada. Gulosaurus was first named by Robin S. Cuthbertson, Anthony P. Russell and Jason S. Anderson in 2013 and the type species is Gulosaurus helmi. [2] The name means 'Helm's wolverine lizard' and refers to the Wolverine Nordic and Mountain Society, who maintain the area around Wapiti Lake where it was found, and to Dr Charles Helm, who is a leading paleontologist around this same area. [3]
Originally Gulosaurus was thought to be either Grippia longirostris or Parvinatator wapitiensis, but as the fossil was incomplete it was uncertain which. In 2013, the other half of the fossil, including its skull, was discovered and this proved it to be a new species entirely, closely related to Grippia and very similar.
Overall, Gulosaurus was similar to Grippia. It was the same size, around 1.5 meters long, and much of the skeleton was the same, namely the ribs and centrum discovered. Also like Grippia, it had pentadactyl limbs rather than exhibiting polyphalangy, as many later ichthyopterygians did. Most of the flipper structure was very similar apart from the first metacarpal, which had a notched peripheral shaft in Gulosaurus but was lunate in Grippia. The skull of Gulosaurus was also very different to that of Grippia - it had cylindrical anterior teeth, although as no Grippia snouts have been discovered, it remains unknown if this was different. The skull also exhibited postfrontal -frontal contact at the rostral limit of the anterior margin of the supratemporal terrace. [2]
Below is a cladogram modified from Cuthbertson et al., 2013. [2]
Ichthyopterygia |
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Ichthyosauria is an order of large extinct marine reptiles sometimes referred to as "ichthyosaurs", although the term is also used for wider clades in which the order resides.
Ichthyopterygia was a designation introduced by Sir Richard Owen in 1840 to designate the Jurassic ichthyosaurs that were known at the time, but the term is now used more often for both true Ichthyosauria and their more primitive early and middle Triassic ancestors.
Tumbler Ridge is a district municipality in the foothills of the B.C. Rockies in northeastern British Columbia, Canada, and a member municipality of the Peace River Regional District. With a population of 2,399 (2021) living in a townsite, the municipality encompasses an area of 1,558 km2 (602 sq mi) of mostly Crown land. The townsite is located near the confluence of the Murray River and Flatbed Creek and the intersection of Highway 52 and Highway 29 and includes the site of the Tumbler Ridge Secondary School and Tumbler Ridge Airport. It is part of the Peace River South provincial electoral district and the Prince George—Peace River—Northern Rockies federal riding.
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Chaohusaurus is an extinct genus of basal ichthyopterygian, depending on definition possibly ichthyosaur, from the Early Triassic of Chaohu and Yuanan, China.
Omphalosaurus is an extinct genus of marine reptile from the Early Triassic to Middle Triassic, thought to be in the order of Ichthyosauria. Most of what is known about Omphalosaurus is based on multiple jaw fragments, ribs, and vertebrae. Specimens of Omphalosaurus have been described from the western United States, Poland, Austria and the island of Spitsbergen off the northern coast of Norway.
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Helveticosaurus is an extinct genus of diapsid marine reptile known from the Middle Triassic of southern Switzerland. It contains a single species, Helveticosaurus zollingeri, known from the nearly complete holotype T 4352 collected at Cava Tre Fontane of Monte San Giorgio, an area well known for its rich record of marine life during the Middle Triassic.
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Phantomosaurus is an extinct genus of ichthyosaur that lived during the late Anisian stage of the Middle Triassic. Fossils have been found in southern Germany. It was discovered in 1965 and named in 1997 as a species of Shastasaurus by Sander in the rocks of the Upper Muschelkalk.
Thaisaurus is an extinct genus of ichthyopterygian marine reptile that lived during the Spathian. Fossils have been found in Thailand.
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The Sulphur Mountain Formation is a geologic formation of Early to Middle Triassic age. It is present on the western edge of the Western Canada Sedimentary Basin in the foothills and Rocky Mountains of western Alberta and northeastern British Columbia. It includes marine fossils from the time shortly after the Permian-Triassic extinction event.
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