Eumetabolodon

Eumetabolodon
Temporal range: Early-?Middle Triassic, 251–244Ma
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Procolophonomorpha
Family: Procolophonidae
Subfamily: Procolophoninae
Genus: Eumetabolodon
Li, 1983
Species
  • E. bathycephalus Li, 1983 (type)
  • "E." dongshengensis Li, 1983

Eumetabolodon is an extinct genus of procolophonine procolophonid parareptile from early and middle Triassic (Induan to earliest Anisian stages) deposits of Nei Mongol, northern China. Two species of Eumetabolodon were named by J. L. Li in 1983 and the type species is Eumetabolodon bathycephalus.[1]

Discovery

The type species is known from the holotype IVPP V6064, a nearly complete skull which was collected in the Zhuengeerqi locality, from the upper Heshanggou Formation (Olenekian and earliest Anisian stages), Ordos Basin. A second specimen, IVPP V6070 was collected in the Zhuengeerqi locality, from the Ermaying Formation (upper Olenekian stage), Ordos Basin. Additional 17 specimens, IVPP V6065-69, V6166 (1&2), V6167, V6168 (1&2), V6169-75, were collected in the Gucheng locality, from the upper Heshanggou Formation, Ordos Basin. "E." dongshengensis is known only from the holotype IVPP V6073, a partial skull including right frontal, prefrontal, lacrimal, maxilla with seven teeth and the right ramus of lower jaw. It was collected in the Wusilangou locality near Dongsheng (also in Nei Mongol), from the Early Triassic Shihtienfeng Formation.[1]

Phylogeny

Recent cladistic analyses suggest that Eumetabolodon is a paraphyletic genus; the type species represents a relatively derived procolophonine, whereas "E." dongshengensis is a more basal procolophonid of the subfamily Theledectinae. The cladogram below follows the topology from a 2012 analysis by Cisneros.[2]

Procolophonidae

Coletta



Pintosaurus



Sauropareion




Phaanthosaurus



Theledectinae

"Eumetabolodon" dongshengensis



Theledectes





Tichvinskia




Leptopleuroninae


Procolophoninae


Timanophon




Kapes



Thelephon






Eumetabolodon bathycephalus




Procolophon



Teratophon



Thelerpeton










References

  1. 1.0 1.1 J. L. Li (1983). "Tooth replacement in a new genus of procolophonid from the Early Triassic of China". Palaeontology 26 (3): 567–583.
  2. Juan Carlos Cisneros (2008). "Phylogenetic relationships of procolophonid parareptiles with remarks on their geological record". Journal of Systematic Palaeontology 6 (3): 345–366. doi:10.1017/S1477201907002350.