Dianmeisaurus

Dianmeisaurus is an extinct genus of pachypleurosaur from the Middle Triassic Guanling Formation in China. The type species is D. gracilis.^[1] An additional species, D. mutaensis, was named in 2024 based on a small skeleton likely belonging to an immature individual.^[2]

Dianmeisaurus Temporal range: Middle Triassic, Anisian PreꞒ Ꞓ O S D C P T J K Pg N
Holotype specimen of D. mutaensis, likely representing an immature individual
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Superorder:	†Sauropterygia
Suborder:	†Pachypleurosauria
Genus:	†Dianmeisaurus Shang & Li, 2015
Type species
†Dianmeisaurus gracilis Shang & Li, 2015
Other species
†D. mutaensis Hu, Li & Liu, 2024

Classification

In their 2024 description of Dianmeisaurus mutaensis, Hu, Li & Liu recovered the two species of Dianmeisaurus as the sister taxon to Panzhousaurus in a clade of basally-branching pachypleurosaurs. In their analyses, they recovered the Pachypleurosauria as the sister taxon to the Nothosauroidea. The results of their phylogenetic analyses are shown in the cladogram below:^[2]

Sauropterygia	Placodus Eosauropterygia Pistosauridae Majiashanosaurus Hanosaurus Nothosauroidea Pachypleurosauria Panzhousaurus Dianmeisaurus gracilis Dianmeisaurus mutaensis Dianopachysaurus Dawazisaurus Keichousaurus Diandongosaurus Odoiporosaurus Anarosaurus Dactylosaurus Serpianosaurus Neusticosaurus Prosantosaurus Qianxisaurus Honghesaurus