Baisesaurus

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Baisesaurus
Temporal range: Early Triassic, 250  Ma
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Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Clade: Ichthyosauromorpha
Genus: Baisesaurus
Ren et al., 2022
Species:
B. robustus
Binomial name
Baisesaurus robustus
Ren et al., 2022

Baisesaurus (meaning "Baise lizard") is an extinct genus of ichthyosauromorph from the early Triassic (Spathian) Luolou Formation of Guangxi, China. The genus contains a single species, B. robustus, known from a partial postcranial skeleton. [1]

Contents

Discovery and naming

The Baisesaurus holotype specimen, CUGW VH107, was discovered in 2018 in a layer of the Luolou Formation in the Nanpanjiang Basin of Zhebao Township, Longlin County, Baise, Guangxi region, China. The specimen consists of assorted ribs, gastralia, a limb element (likely a radius), 12 vertebral centra, and seven neural arches.

In 2022, Ren et al. described Baisesaurus robustus, a new genus and species of basal ichthyosauromorph. The generic name, "Baisesaurus", combines a reference to the type locality in Baise, China, with the Greek "saurus", meaning "lizard". The specific name, "robustus", means "robust". [1]

Description

Baisesaurus was likely at least 3 m (9.8 ft) long. It was more similar to Utatsusaurus than to any other ichthyosauromorph, with similar size and anatomical traits. It can be inferred from related animals that Baisesaurus was a strong swimmer with long, compact forelimb bones. [1]

Classification

Baisesaurus likely represents a basal member of the clade Ichthyosauromorpha. The describing authors explain that it may represent a member of the Ichthyopterygia. However, such a classification is highly tentative. [1]

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References

  1. 1 2 3 4 Ren, Jicheng; Jiang, Haishui; Xiang, Kunpeng; Sullivan, Corwin; He, Yongzhong; Cheng, Long; Han, Fenglu (2022-04-07). "A new basal ichthyosauromorph from the Lower Triassic (Olenekian) of Zhebao, Guangxi Autonomous Region, South China". PeerJ . 10: e13209. doi: 10.7717/peerj.13209 . ISSN   2167-8359. PMC   8995025 . PMID   35415016.