Chusaurus is an extinct genus of pachypleurosaurid known from the Early Triassic Nanzhang-Yuan’an Fauna in the South China block. The two known specimens of Chusaurus were found in Hubei Province, China, dating back to the Olenekian age of the Early Triassic period. The genus contains a single species, Chusaurus xiangensis[1][2]
The fossils of Chusaurus were described in 2023 by a team of paleontologists from the China University of Geosciences and the Hubei Geological Museum. They were collected from the Jialingjiang Formation, a sedimentary rock unit that preserves a rich diversity of marine reptiles from the Early Triassic.[3] The genus name, Chusaurus", honors Chu Zhonglin, a Chinese paleontologist who contributed to the study of Triassic marine reptiles. The species name, "xiangensis", refers to the Xiang River, which flows through Hubei Province.[1]
Descriptionedit
Chusaurus xiangensis (foreground)
Chusaurus is a small-sized sauropterygian, with an estimated total length of about 60 cm. It has a slender body, a short neck, and four paddle-like limbs. The skull is poorly preserved, but it shows some features that distinguish it from other pachypleurosaurids, such as a large external naris, a reduced premaxilla, and a long maxilla. The teeth are conical and slightly curved, indicating a carnivorous diet.[1]
The most distinctive feature of Chusaurus is its short neck, which comprises only 17 cervical vertebrae. This is much less than other pachypleurosaurids, which have 24 to 28 cervical vertebrae, and less than the distantly related plesiosaurs, which have 28 to 76 cervical vertebrae. The cervical vertebrae of Chusaurus are also relatively short and wide, with well-developed neural spines and ribs. The dorsal vertebrae are similar to those of other pachypleurosaurids, but they have more pronounced transverse processes. The caudal vertebrae are not well preserved, but they seem to be elongated and slender.[1]
The limbs of Chusaurus are adapted for swimming, with long and narrow bones and digits. The humerus and femur are similar in shape and size, but the humerus has a larger head and a more prominent deltopectoral crest. The radius and ulna are shorter than the humerus, and the tibia and fibula are shorter than the femur. The manus and pes have five digits each, with the fifth digit being the longest. The phalanges are flattened and expanded distally, forming paddle-like structures.[1]
Referencesedit
^ abcdeLiu et al. (2023). A new short-necked pachypleurosaurid sauropterygian from the Early Triassic of China. BMC Evolutionary Biology, 23(1), 150.
^Liu, Qi-Ling; Cheng, Long; Stubbs, Thomas L.; Moon, Benjamin C.; Benton, Michael J.; Yan, Chun-Bo; Tian, Li (August 31, 2023). "Rapid neck elongation in Sauropterygia (Reptilia: Diapsida) revealed by a new basal pachypleurosaur from the Lower Triassic of China". BMC Ecology and Evolution. 23 (1): 44. doi:10.1186/s12862-023-02150-w. PMC10469986. PMID 37648992.
^Interesting Engineering (2023). Fossils of Ancient Marine Reptile Discovered in China.
April 10, 2024
chusaurus, extinct, genus, pachypleurosaurid, known, from, early, triassic, nanzhang, yuan, fauna, south, china, block, known, specimens, were, found, hubei, province, china, dating, back, olenekian, early, triassic, period, genus, contains, single, species, x. Chusaurus is an extinct genus of pachypleurosaurid known from the Early Triassic Nanzhang Yuan an Fauna in the South China block The two known specimens of Chusaurus were found in Hubei Province China dating back to the Olenekian age of the Early Triassic period The genus contains a single species Chusaurus xiangensis 1 2 ChusaurusTemporal range Early Triassic Spathian PreꞒ Ꞓ O S D C P T J K Pg N Two specimens of ChusaurusScientific classificationDomain EukaryotaKingdom AnimaliaPhylum ChordataClass ReptiliaSuperorder SauropterygiaFamily PachypleurosauridaeGenus ChusaurusLiu et al 2023Species C xiangensisBinomial name Chusaurus xiangensisLiu et al 2023Discovery and naming editThe fossils of Chusaurus were described in 2023 by a team of paleontologists from the China University of Geosciences and the Hubei Geological Museum They were collected from the Jialingjiang Formation a sedimentary rock unit that preserves a rich diversity of marine reptiles from the Early Triassic 3 The genus name Chusaurus honors Chu Zhonglin a Chinese paleontologist who contributed to the study of Triassic marine reptiles The species name xiangensis refers to the Xiang River which flows through Hubei Province 1 Description edit nbsp Chusaurus xiangensis foreground Chusaurus is a small sized sauropterygian with an estimated total length of about 60 cm It has a slender body a short neck and four paddle like limbs The skull is poorly preserved but it shows some features that distinguish it from other pachypleurosaurids such as a large external naris a reduced premaxilla and a long maxilla The teeth are conical and slightly curved indicating a carnivorous diet 1 The most distinctive feature of Chusaurus is its short neck which comprises only 17 cervical vertebrae This is much less than other pachypleurosaurids which have 24 to 28 cervical vertebrae and less than the distantly related plesiosaurs which have 28 to 76 cervical vertebrae The cervical vertebrae of Chusaurus are also relatively short and wide with well developed neural spines and ribs The dorsal vertebrae are similar to those of other pachypleurosaurids but they have more pronounced transverse processes The caudal vertebrae are not well preserved but they seem to be elongated and slender 1 The limbs of Chusaurus are adapted for swimming with long and narrow bones and digits The humerus and femur are similar in shape and size but the humerus has a larger head and a more prominent deltopectoral crest The radius and ulna are shorter than the humerus and the tibia and fibula are shorter than the femur The manus and pes have five digits each with the fifth digit being the longest The phalanges are flattened and expanded distally forming paddle like structures 1 References edit a b c d e Liu et al 2023 A new short necked pachypleurosaurid sauropterygian from the Early Triassic of China BMC Evolutionary Biology 23 1 150 Liu Qi Ling Cheng Long Stubbs Thomas L Moon Benjamin C Benton Michael J Yan Chun Bo Tian Li August 31 2023 Rapid neck elongation in Sauropterygia Reptilia Diapsida revealed by a new basal pachypleurosaur from the Lower Triassic of China BMC Ecology and Evolution 23 1 44 doi 10 1186 s12862 023 02150 w PMC 10469986 PMID 37648992 Interesting Engineering 2023 Fossils of Ancient Marine Reptile Discovered in China Retrieved from https en wikipedia org w index php title Chusaurus amp oldid 1216570342, wikipedia, wiki, book, books, library,
