Biology:Aspidosaurus

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Short description: Extinct genus of amphibians

Aspidosaurus
Temporal range: Late Carboniferous - Early Permian
Aspidosaurus Skull
Scientific classification e
Kingdom: Animalia
Phylum: Chordata
Class: Amphibia
Order: †Temnospondyli
Family: †Dissorophidae
Genus: †Aspidosaurus
Broili, 1904
Species
  • †A. chiton Broili, 1904 (type)
  • †A. apicalis
  • †A. crucifer
  • †A. glascocki
  • †A. binasser Berman and Lucas, 2003
Synonyms
  • Alegeinosaurus Case, 1911

Aspidosaurus is an extinct genus of dissorophoid temnospondyl within the family Dissorophidae.

Description

Like other dissorophids, Aspidosaurus species had a single row of plates formed by expansions of the neural spines.[1]

Taxonomy

In 1911, Paul Miller discovered the remains of various dissorophid bones in New Mexico that were attributed to a new species, Aspidosaurus novomexicanus. The skull closely resembled that of a specimen of Cacops aspidephorus found in Texas but the arrangement of ridges in the otic region was different. The teeth found were slender and conical and all of an approximately equal size. The vertebral column, pelvis and limb bones were also similar but the new specimen was distinguished from Cacops by the armour, the single row of vertical plates that were originally attached to the neural spines of the vertebrae.[1] A. novomexicanus was later attributed to the genus Broiliellus. More recently, "A." novomexicanus has been removed from Broiliellus and classified as a closer relative of Cacops. The original specimen is now housed in the University of California Museum of Paleontology and is referred to as the "Rio Arriba taxon" because of its uncertain phylogenetic placement.[2]

The genus Alegeinosaurus Case, 1911 was synonymized with Aspidosaurus by Gee (2018) based on a redescription of the holotype.[3]

Phylogeny

Below is a cladogram from Schoch (2012) in which valid Aspidosaurus species are found to be basal dissorophids and "Aspidosaurus" novomexicanus -the Rio Arriba taxon- nests within the subfamily Cacopinae:[2]

Dissorophoidea
Micromelerpetontidae
 

Micromelerpeton

 
 
 
Amphibamidae
 

Platyrhinops

 
 

Doleserpeton

 
 
Olsoniformes
Trematopidae
 

Ecolsonia

 
 

Fedexia

 
 
 

Tambachia

 
 

Anconastes

 
 
 

Phonerpeton

 
 

Acheloma

 
 
 
 
Dissorophidae
 

Platyhystrix

 
 

Aspidosaurus

 
 
 

Conjunctio

 
Dissorophinae
 

Dissorophus

 
 

Broiliellus texensis

 
 

Broiliellus brevis

 
 

Broiliellus olsoni

 
 
Cacopinae
 

Brevidorsum

 
 
 

Admiral taxon

 
 

Rio Arriba taxon

 
 
 

Cacops morrisi

 
 

Cacops aspidephorus

 
 
 

Kamacops

 
 

Zygosaurus

 
 
 
 
 
 
 
 
 
 

References

  1. ↑ 1.0 1.1 A Description of Aspidosaurus novomexicanus Williston Permo-Carboniferous Vertebrates from New Mexico, p7-11. Retrieved 2011-09-11.
  2. ↑ 2.0 2.1 Schoch, R. R. (2012). "Character distribution and phylogeny of the dissorophid temnospondyls". Fossil Record 15 (2): 121–137. doi:10.1002/mmng.201200010. 
  3. ↑ Bryan M. Gee (2018). "Reappraisal of the early Permian dissorophid Alegeinosaurus from Texas, USA". PalZ 92 (4): 661–669. doi:10.1007/s12542-018-0421-9. 

Wikidata ☰ Q3564834 entry