Dissorophoidea is a

clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...

of medium-sized,

temnospondyl Temnospondyli (from Greek language, Greek τέμνειν, ''temnein'' 'to cut' and σπόνδυλος, ''spondylos'' 'vertebra') or temnospondyls is a diverse ancient order (biology), order of small to giant tetrapods—often considered Labyrinth ...

amphibians that appeared during the Moscovian in

Euramerica Laurasia () was the more northern of two large landmasses that formed part of the Pangaea supercontinent from around ( Mya), the other being Gondwana. It separated from Gondwana (beginning in the late Triassic period) during the breakup of Pa ...

, and continued through to the

Late Permian Late or LATE may refer to: Everyday usage * Tardy, or late, not being on time * Late (or the late) may refer to a person who is dead Music * ''Late'' (The 77s album), 2000 * Late (Alvin Batiste album), 1993 * Late!, a pseudonym used by Dave Groh ...

and the

Early Triassic The Early Triassic is the first of three epochs of the Triassic Period of the geologic timescale. It spans the time between 251.9 Ma and Ma (million years ago). Rocks from this epoch are collectively known as the Lower Triassic Series, which ...

Gondwana Gondwana ( ; ) was a large landmass, sometimes referred to as a supercontinent. The remnants of Gondwana make up around two-thirds of today's continental area, including South America, Africa, Antarctica, Australia (continent), Australia, Zea ...

. They are distinguished by various details of the skull, and many species seem to have been well adapted for life on land. Dissorophoid diversity was highest in the Permian; some of the more diverse families within the group include Dissorophidae (toad-like amphibians with armored scutes along their backbone), Trematopidae (terrestrial predators with large triangular skulls), and Branchiosauridae (small neotenic amphibians with large external gills). The small Permo-Carboniferous Micromelerpetontidae are another example of neotenic dissorophoids. Many small dissorophoids with short rounded skulls were historically known as "

amphibamids The Amphibamidae are an ancient Family (biology), family of Dissorophoidea, dissorophoid temnospondyls known from Late Carboniferous-Early Permian strata in the United States. Classification Amphibamidae has traditionally included small-bodied ...

"; in 2018, the name

Amphibamiformes Amphibamiformes is an unranked clade with Dissorophoidea created by Schoch (2018). It encompasses all of the taxa traditionally considered to be "amphibamids" (subsequently restricted to '' Doleserpeton annectens'' and '' Amphibamus grandiceps'' ...

was erected for a clade equivalent to the broad historical definition of "Amphibamidae". Since 2008, a consensus of early amphibian researchers consider

Lissamphibia The Lissamphibia (from Greek λισσός (lissós, "smooth") + ἀμφίβια (amphíbia), meaning "smooth amphibians") is a group of tetrapods that includes all modern amphibians. Lissamphibians consist of three living groups: the Salientia ( ...

(modern amphibians) to be part of this clade. There is a large degree of similarity between lissamphibians (for which the oldest known fossils are Early Triassic) and certain Early Permian amphibamiforms, such as ''

Gerobatrachus ''Gerobatrachus'' is an extinct genus of amphibamid temnospondyl (represented by the type species ''Gerobatrachus hottoni'') that lived in the Early Permian, approximately 290 million years ago (Ma), in the area that is now Baylor County, Texa ...

'' and ''

Doleserpeton ''Doleserpeton'' is an extinct, monospecific genus of dissorophoidean temnospondyl within the family (biology), family Amphibamidae that lived during the Upper Permian, 285 million years ago. ''Doleserpeton'' is represented by a single species, ' ...

''. A few authors still dispute affinities between dissorophoids and lissamphibians.

Taxonomy

* † Micromelerpetontidae * Xerodromes ** †

Olsoniformes Olsoniformes is an extinct clade of dissorophoid temnospondyls, including the families Dissorophidae and Trematopidae. Most members of the clade were highly adapted to a terrestrial lifestyle. The clade was named in 2008 and is defined as the ...

*** † Dissorophidae *** † Trematopidae **

Schoch, R.R. (2018
The putative lissamphibian stem-group: phylogeny and evolution of the dissorophoid temnospondyls
''Journal of Paleontology''. Online edition. doi:10.1017/jpa.2018.67. *** †

Amphibamidae The Amphibamidae are an ancient family of dissorophoid temnospondyls known from Late Carboniferous-Early Permian strata in the United States. Classification Amphibamidae has traditionally included small-bodied, terrestrial dissorophoids. The ...

*** † Branchiosauridae *** †

Micropholidae The Micropholidae are an extinct family of dissorophoid temnospondyls known from Late Carboniferous to Early Triassic The Early Triassic is the first of three epochs of the Triassic Period of the geologic timescale. It spans the time between ...

*** †''

Eoscopus ''Eoscopus'' is an extinct genus of dissorophoidean euskelian temnospondyl in the family Micropholidae. It is known from Hamilton Quarry, a Late Carboniferous lagerstätte A Fossil-Lagerstätte (, from ''Lager'' 'storage, lair' '' Stätte ...

'' *** †''

Georgenthalia ''Georgenthalia'' is an extinct genus of dissorophoid temnospondyl from the Lower Permian. It is an amphibamid which lived in what is now the Thuringian Forest of central Germany. It is known from the holotype MNG 11135, a small, complete skul ...

'' *** †''

'' *** †'' Nanobamus'' *** †''

Platyrhinops ''Platyrhinops'' is an extinct genus amphibamid temnospondyl from the Late Carboniferous (late Westphalian stage) of Ohio and the Czech Republic The Czech Republic, also known as Czechia, and historically known as Bohemia, is a landloc ...

'' *** †'' Plemmyradytes'' *** †'' Rubeostratilia'' ***

(according to the consensus position) **** †

Allocaudata The Albanerpetontidae (also spelled Albanerpetidae and Albanerpetonidae) are an extinct family of small amphibians, native to the Northern Hemisphere during the Mesozoic and Cenozoic. The only members of the order Allocaudata, they are thought to ...

/ †

Albanerpetontidae The Albanerpetontidae (also spelled Albanerpetidae and Albanerpetonidae) are an extinct family of small amphibians, native to the Northern Hemisphere during the Mesozoic and Cenozoic. The only members of the order Allocaudata, they are thought to ...

****

Gymnophiona Caecilians (; ) are a group of limbless, vermiform (worm-shaped) or serpentine (snake-shaped) amphibians with small or sometimes nonexistent eyes. They mostly live hidden in soil or in streambeds, and this cryptic lifestyle renders caecilians ...

(total group of

caecilians Caecilians (; ) are a group of limbless, vermiform (worm-shaped) or serpentine (snake-shaped) amphibians with small or sometimes nonexistent eyes. They mostly live hidden in soil or in streambeds, and this cryptic lifestyle renders caecilians ...

) **** Batrachia *****

Salientia The Salientia (Latin ''salire'', ''salio'' meaning "to jump") are a total group of amphibians that includes the order Anura, the frogs and toads, and various extinct proto-frogs that are more closely related to the frogs than they are to the ...

(total group of

frogs A frog is any member of a diverse and largely semiaquatic group of short-bodied, tailless amphibian vertebrates composing the order Anura (coming from the Ancient Greek , literally 'without tail'). Frog species with rough skin texture due to ...

) *****

Caudata The Caudata are a group of amphibians containing the extant salamanders (the order Urodela) and all extinct species of amphibians more closely related to salamanders than to frogs. They are typically characterized by a superficially lizard-lik ...

(total group of

salamanders Salamanders are a group of amphibians typically characterized by their lizard-like appearance, with slender bodies, blunt snouts, short limbs projecting at right angles to the body, and the presence of a tail in both larvae and adults. All t ...

)

Phylogeny

An extensive phylogenetic analysis of dissorophoids conducted in 2016 and 2018 found that the families Dissorophidae and Trematopidae are more closely related to each other than either is to the family

. Following a 2008 study, the Dissorophidae-Trematopidae clade was called

. Below is the

cladogram A cladogram (from Greek language, Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an Phylogenetic tree, evolutionary tree because it does not s ...

from the 2018 analysis:

References

* Huttenlocker, Adam. 2007
Dissorophoidea

Tree of Life Web Project The Tree of Life Web Project (ToL) is an Internet project providing information about the diversity and phylogeny of life on Earth. This collaborative peer reviewed project began in 1995, and is written by biologists from around the world. The s ...

* Laurin, M. and Steyer, J-S, 2000
Phylogeny and Apomorphies of Temnospondyls

(reviewed) * Reisz, Robert (no date),
Biology 356 - Major Features of Vertebrate Evolution - The Origin of Tetrapods and Temnospondyls

References

External links

- Palaeos

- Mikko's Phylogeny Archive {{Taxonbar, from=Q137426 Vertebrate superfamilies Pennsylvanian first appearances