Temporal range: Late Carboniferous - Early Triassic, 310–249Ma
Possible descendant taxon Lissamphibia survives to present.
|Skeleton of Cacops aspidephorus in the Field Museum|
|Class:||"Amphibia" (wide sense)|
Dissorophoideans are a clade of medium-sized, temnospondyl amphibians that appeared during the Late Pennsylvanian in Euramerica, and continued through to the Late Permian and even possibly the Early Triassic of Gondwana (if Micropholis belongs here). They are distinguished by various details of the skull, and many forms seem to have been well adapted for life on land.
It has been suggested that they may be ancestral to the Frogs (Reisz, no date) or even the Lissamphibia as a whole, in which case the latter would be included in this clade.
An extensive phylogenetic analysis of dissorophoids conducted in 2012 found that the families Dissorophidae and Trematopidae are more closely related to each other than either is to the family Amphibamidae. Following a 2008 study, the Dissorophidae-Trematopidae clade was called Olsoniformes. Below is the cladogram from the 2012 analysis:
References and Reliable Link References
- Huttenlocker, Adam. 2007. Dissorophoidea Tree of Life Web Project
- Laurin, M. and Steyer, J-S, 2000, Phylogeny and Apomorphies of Temnospondyls Tree of Life Web Project (reviewed)
- Reisz, Robert, (no date), Biology 356 - Major Features of Vertebrate Evolution - The Origin of Tetrapods and Temnospondyls