Biology:Luxisaurus

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Short description: Extinct genus of tanystropheid reptiles

Luxisaurus
Temporal range: Middle Triassic (Anisian)
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Scientific classification edit
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Clade: Archosauromorpha
Family: †Tanystropheidae
Genus: †Luxisaurus
Species:
†L. terrestris
Binomial name
†Luxisaurus terrestris
Lu & Liu, 2023

Luxisaurus (meaning "Luxi lizard") is an extinct genus of tanystropheid archosauromorph reptile from the Middle Triassic (Anisian) Guanling Formation of China. The genus contains a single species, L. terrestris, known from an articulated partial skeleton. Luxisaurus is hypothesized to have lived a more terrestrial lifestyle than many other tanystropheids, which may have been aquatic.[1]

Discovery and naming

The Luxisaurus holotype specimen, HFUT SML-21-08-001, was discovered in sediments of the Guanling Formation (Upper Member), dated to the Anisian age (Pelsonian substage) of the middle Triassic period, near Suomeiluo in Luxi County, Yunnan Province, China. The articulated incomplete specimen consists of most of both forelimbs (missing their proximal ends), most of both hindlimbs (missing part of the right femur), gastralia, elements of the pelvic girdle, part of the last dorsal vertebra, two sacral vertebrae with sacral ribs, and several proximal caudal vertebrae.[1]

In 2023, Lu & Liu described Luxisaurus terrestris as a new genus and species of tanystropheid archosauromorph based on these fossil remains. The generic name, "''Luxisaurus", combines a reference to the type locality in Luxi County with the Greek "saurus", meaning "lizard". The specific name, "terrestris", references the hypothesized terrestrial lifestyle of Luxisaurus.[1]

Classification

Lu & Liu (2023) recovered Luxisaurus as a basal tanystropheid member of the Archosauromorpha, as the sister taxon to all other tanystropheids besides Fuyuansaurus, which is the basalmost member of the clade. They further hypothesized that, since the basalmost members of the Tanystropheidae have been found in South China, the clade may have originated here before dispersing globally. The results of their phylogenetic analyses are shown in the cladogram below:[1]

Archosauromorpha
 

Protorosaurus

 
 
 

Crocopoda

 
 
 

Jesairosaurus

 
 
Dinocephalosauridae
 

Dinocephalosaurus

 
 

Pectodens

 
 
Tanystropheidae
 

Fuyuansaurus

 
 
 

Luxisaurus

 
 
 

Sclerostropheus

 
 

Elessaurus

 
 

Langobardisaurus

 
 

Tanytrachelos

 
 

AMNH FARB 7206 ((an unnamed Tanytrachelos-like tanystropheid from New Jersey)

 
 

Ozimek

 
 
 
 
 
 

Macrocnemus bassanii

 
 
 

Macrocnemus obristi

 
 

Macrocnemus fuyuanensis

 
 
 
 
 
 
 
 

Augustaburiania

 
 

Amotosaurus

 
 
 
 

Raibliania

 
 

Tanystropheus longobardicus

 
 

GMPKU P 1527 (T. cf. hydroides)

 
 

Tanystropheus hydroides

 
 
 
 
 
 
 
 
 

References

  1. ↑ 1.0 1.1 1.2 1.3 Lu, Yu-Ting; Liu, Jun (2023-10-02). "A new tanystropheid (Diapsida: Archosauromorpha) from the Middle Triassic of SW China and the biogeographical origin of Tanystropheidae" (in en). Journal of Systematic Palaeontology 21 (1). doi:10.1080/14772019.2023.2250778. ISSN 1477-2019. 

Wikidata ☰ Q122917339 entry