''Almasaurus'' is an extinct
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
of
trematosauria
Trematosauria is one of two major groups of temnospondyl amphibians that survived the Permian-Triassic extinction event, the other (according to Yates and Warren 2000) being the Capitosauria. The trematosaurs were a diverse and important group ...
n
temnospondyl
Temnospondyli (from Greek language, Greek τέμνειν, ''temnein'' 'to cut' and σπόνδυλος, ''spondylos'' 'vertebra') is a diverse order (biology), order of small to giant tetrapods—often considered Labyrinthodontia, primitive amphi ...
within the
family
Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...
Latiscopidae
Latiscopidae is an extinct family of Mesozoic Era amphibian Temnospondyli
Temnospondyli (from Greek τέμνειν, ''temnein'' 'to cut' and σπόνδυλος, ''spondylos'' 'vertebra') is a diverse order of small to giant tetrapods—ofte ...
. It is known from several skulls and some postcranial material found from the
Argana Formation in
Morocco
Morocco (),, ) officially the Kingdom of Morocco, is the westernmost country in the Maghreb region of North Africa. It overlooks the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria to ...
, which dates back to the
Late Triassic
The Late Triassic is the third and final epoch (geology), epoch of the Triassic geologic time scale, Period in the geologic time scale, spanning the time between annum, Ma and Ma (million years ago). It is preceded by the Middle Triassic Epoch ...
.
When it was first named in 1972, ''Almasaurus'' was placed within its own
superfamily
SUPERFAMILY is a database and search platform of structural and functional annotation for all proteins and genomes. It classifies amino acid sequences into known structural domains, especially into SCOP superfamilies. Domains are functional, str ...
, the Almasauroidea.
Although the related latiscopid ''
Latiscopus disjunctus'' possesses
exoccipitals that are underplated (a feature that suggests that it is a member of the family
Trematosauridae
Trematosauridae are a family of large marine temnospondyl amphibians with many members. They first appeared during the Induan age of the Early Triassic, and existed until around the Carnian stage of the Late Triassic, although by then they wer ...
)
''Almasaurus'' is not considered to be a trematosaurid because it lacks such underplating.
''Almasaurus'' was considered to be a
capitosauria
Capitosauria is an extinct group of large temnospondyl amphibians with simplified stereospondyl vertebrae. Mainly living as piscivores in lakes and rivers, the Capitosauria and its sister taxon Trematosauria were the only major labyrinthodonts t ...
n by Warren & Black (1985) because it shared several characters with the group, including a deeply notched
squamosal The squamosal is a skull bone found in most reptiles, amphibians, and birds. In fishes, it is also called the pterotic bone.
In most tetrapods, the squamosal and quadratojugal The quadratojugal is a skull bone present in many vertebrates, including ...
and a
lacrimal flexure, while supposedly exhibiting none of the characters associated with trematosaurians.
[ However, more recent studies have concluded that ''Almasaurus'' is either a temnospondyl more basal than the clade formed from the dichotomy between Capitosauria and Trematosauria] or that the genus is closely related to the trematosaurian family Metoposauridae
Metoposauridae is an extinct family of trematosaurian temnospondyls. The family is known from the Triassic period. Most members are large, approximately long and could reach 3 m long.Brusatte, S. L., Butler R. J., Mateus O., & Steyer S. J. (201 ...
, perhaps being a sister taxon
In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree.
Definition
The expression is most easily illustrated by a cladogram:
Taxon A and t ...
of it.
A temnospondyl genus described in 2000, '' Rileymillerus'', is thought to be closely related to ''Almasaurus''.
Below is a cladogram
A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to d ...
showing the phylogenetic position of ''Almasaurus'', from Schoch (2008):[
]
See also
* Prehistoric amphibian
This list of prehistoric amphibians is an attempt to create a comprehensive listing of all Genus, genera from the fossil record that have ever been considered to be amphibians, excluding purely vernacular terms. The list includes all commonly accep ...
* List of prehistoric amphibians
This list of prehistoric amphibians is an attempt to create a comprehensive listing of all genera from the fossil record that have ever been considered to be amphibians, excluding purely vernacular terms. The list includes all commonly accepted g ...
References
External links
''Almasaurus''
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 ...
Triassic temnospondyls of Africa
Early Triassic amphibians of Africa
Fossil taxa described in 1972
{{Triassic-animal-stub