The Amphibamidae are an extinct

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

dissorophoid Dissorophoideans are a clade of medium-sized, temnospondyl amphibians that appeared during the Moscovian in Euramerica, and continued through to the Late Permian and the Early Triassic of Gondwana. They are distinguished by various details of the ...

temnospondyl Temnospondyli (from Greek τέμνειν, ''temnein'' 'to cut' and σπόνδυλος, ''spondylos'' 'vertebra') is a diverse order of small to giant tetrapods—often considered primitive amphibians—that flourished worldwide during the Carbo ...

s known from Late Carboniferous- Early Permian strata in the United States.

Classification

Amphibamidae has traditionally included small-bodied, terrestrial dissorophoids. The name is attributed to Moodie (1909), but it was rarely used because it originally referred only to ''

Amphibamus ''Amphibamus'' is a genus of amphibamid temnospondyl amphibians from the Carboniferous (middle Pennsylvanian) of North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisp ...

''. Similar monogeneric families were also erected for other small, terrestrial dissorophoids (e.g., Doleserpetontidae), and most of the taxa now recognized as amphibamiforms were placed within the

Dissorophidae Dissorophidae is an extinct family of medium-sized, temnospondyl amphibians that flourished during the late Carboniferous and early Permian periods. The clade is known almost exclusively from North America. History of study Dissorophidae is a ...

. Clack & Milner (1993) revived the Amphibamidae to include ''Amphibamus,

Platyrhinops ''Platyrhinops'' is an extinct genus amphibamid temnospondyl from the Late Carboniferous (late Westphalian stage) of Ohio and the Czech Republic. It is known from many partial skeletons from the Linton site in Saline Township, Ohio and at lea ...

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

,'' and ''

Tersomius ''Tersomius'' is an extinct genus of dissorophoid temnospondyl within the family Micropholidae. It is known from the early Permian of North America (Oklahoma and Texas). History of study ''Tersomius'' was first named in 1910 by American paleo ...

'.'' Daly (1994) further expanded the composition of the Amphibamidae to include the newly described ''Eoscopus'' as well as the Early Triassic form ''Micropholis''. She suggested that the micromelerpetids were also amphibamids, which has not been validated by more recent workers. Subsequent phylogenetic work verified the monophyly of the Amphibamidae, with recent analyses also recovering the

branchiosaurids Branchiosauridae is an extinct family of small amphibamiform temnospondyls with external gills and an overall juvenile appearance. The family has been characterized by hundreds of well-preserved specimens from the Permo-Carboniferous of Middle E ...

nested within the amphibamids. Schoch (2018) erected the new clade

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'' ...

to include the traditional amphibamids and the nested branchiosaurids and subsequently restricted the Amphibamidae to two taxa: ''Doleserpeton annectens'' from the Dolese Brothers Limestone Quarry near Richards Spur, Oklahoma and ''Amphibamus grandiceps'' from Mazon Creek, Illinois. These taxa are united by several features, such as a medially expanded choana.

Phylogeny of amphibamiforms from Schoch (2018)

Relationship to the Batrachia

The Amphibamidae have typically been recovered close to some or all of the lissamphibian crown. Until the description of ''

Gerobatrachus ''Gerobatrachus'' is an extinct genus of Amphibamidae, 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 ...

'', ''Doleserpeton'' was considered to be the closest extinct relative to the crown group. Below is a modified cladogram from Anderson et al. (2008) showing Batrachia nested in the Amphibamidae, with ''Gerobatrachus'' as the sister taxon of

Batrachia The Batrachia are a clade of amphibians that includes frogs and salamanders, but not caecilians nor the extinct allocaudates. The name Batrachia was first used by French zoologist Pierre André Latreille in 1800 to refer to frogs, but has more ...

(anurans and caudates) and ''Doleserpeton'' and ''Amphibamus'' as successive outgroups: There is continued debate over the origin of lissamphibians, including whether they are monophyletic or whether batrachians and caecilians are descended from different clades of tetrapods or temnospondyls. If they are monophyletic, there is also a debate about which clade they are nested in, with some hypotheses suggesting a

lepospondyl Lepospondyli is a diverse taxon of early tetrapods. With the exception of one late-surviving lepospondyl from the Late Permian of Morocco (''Diplocaulus minumus''), lepospondyls lived from the Early Carboniferous ( Mississippian) to the Early Per ...

origin, in which case amphibamids would not be closely related to any extant amphibians.

References

External links

Amphibamidae
in the

Paleobiology Database The Paleobiology Database is an online resource for information on the distribution and classification of fossil animals, plants, and microorganisms. History The Paleobiology Database (PBDB) originated in the NCEAS-funded Phanerozoic Marine Pale ...

{{Taxonbar, from=Q2844161 Dissorophids Prehistoric amphibian families Permian temnospondyls Carboniferous temnospondyls Carboniferous amphibians of North America Permian amphibians of North America