''Broiliellus'' is an extinct

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

dissorophoid Dissorophoidea is 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 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 ...

within the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Dissorophidae Dissorophidae is an extinct family of medium-sized temnospondyls 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 diverse cla ...

. ''Broiliellus'' is most closely related to the genus ''

Dissorophus ''Dissorophus'' (DI-soh-ROH-fus) (meaning "double roof" for two layers of armor) is an extinct genus of temnospondyl amphibian that lived during the Early Permian Period about 273 million years ago. Its fossils have been found in Texas and in Ok ...

'', and both have been placed in the subfamily Dissorophinae. ''Broiliellus'' is known from five species from the

Early Permian 01 or 01 may refer to: * The year 2001, or any year ending with 01 * The month of January * 1 (number) Music * '01 (Richard Müller album), ''01'' (Richard Müller album), 2001 * 01 (Urban Zakapa album), ''01'' (Urban Zakapa album), 2011 * ''01011 ...

: the

type species In International_Code_of_Zoological_Nomenclature, zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the spe ...

is ''Broiliellus texensis,'' and the other species are ''Broiliellus brevis,'' ''Broiliellus olsoni, Broiliellus arroyoensis,'' and ''Broiliellus reiszi''. An additional species, ''Broiliellus novomexicanus'', which was originally named ''

Aspidosaurus ''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.

novomexicanus'', is now thought to fall outside the genus as a member of the subfamily

Eucacopinae Eucacopinae is an extinct clade (evolutionary grouping) of dissorophid temnospondyls. Eucacopines differ from the other main group of dissorophids, the Dissorophinae, in having more lightly built skeletons and more knobby skulls. The subfamily ...

History of study

''Broiliellus'' was first named by American paleontologist S.W. Williston in 1914 based on two nearly complete skulls in articulation with postcranial material from the early Permian of Texas; this species was given the name ''Broiliellus texensis'', the genus name being for the German paleontologist Ferdinand Broili, and the species name being for the geographic provenance. The holotype is currently reposited in the

Field Museum The Field Museum of Natural History (FMNH), also known as The Field Museum, is a natural history museum in Chicago, Illinois, and is one of the largest such museums in the world. The museum is popular for the size and quality of its educationa ...

. A second species, ''Broiliellus brevis'', from the Archer City bonebed in Texas was named in 1964 by Canadian paleontologist Robert Carroll; the holotype of this species is currently reposited in the

Museum of Comparative Zoology The Museum of Comparative Zoology (formally the Agassiz Museum of Comparative Zoology and often abbreviated to MCZ) is a zoology museum located on the grounds of Harvard University in Cambridge, Massachusetts. It is one of three natural-history r ...

. Two more species were named in 1967 by American paleontologist Robert DeMar, ''Broiliellus olsoni'' and ''Broiliellus arroyoensis'', both from Texas. The most recent species to be described was ''Broiliellus reiszi'' in 2013 by Canadian paleontologist Robert Holmes and colleagues.

Phylogeny

The

phylogenetic In biology, phylogenetics () is the study of the evolutionary history of life using observable characteristics of organisms (or genes), which is known as phylogenetic inference. It infers the relationship among organisms based on empirical dat ...

analysis of Schoch (2012) found that ''Broiliellus'' was most closely related to ''Dissorophus''. However, the three species of ''Broiliellus'' did not form their own

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 ...

, but rather a

polytomy An internal node of a phylogenetic tree is described as a polytomy or multifurcation if (i) it is in a rooted tree and is linked to three or more child subtrees or (ii) it is in an unrooted tree and is attached to four or more branches. A tree ...

(unresolved evolutionary relationship) with ''Dissorophus''. Holmes et al. (2013) named a new species of ''Broiliellus'', ''Broiliellus reiszi''. They performed two phylogenetic analyses using the data matrix of Schoch (2012). This analysis yielded more resolved topology and a

monophyletic In biological cladistics for the classification of organisms, monophyly is the condition of a taxonomic grouping being a clade – that is, a grouping of organisms which meets these criteria: # the grouping contains its own most recent co ...

''Broiliellus.'' 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 that analysis:

References

{{Taxonbar, from=Q1965407 Dissorophidae Cisuralian amphibians of North America Prehistoric tetrapod genera Fossil taxa described in 1914 Taxa named by Samuel Wendell Williston Prehistoric amphibian genera