''Siderops'' (from the Greek sideros meaning “iron” and -ops meaning “face” ) 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 ...

of chigutisaurid

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 ...

from

Early Jurassic The Early Jurassic Epoch (geology), Epoch (in chronostratigraphy corresponding to the Lower Jurassic series (stratigraphy), Series) is the earliest of three epochs of the Jurassic Period. The Early Jurassic starts immediately after the Triassic� ...

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

, containing the species ''S. kehli'' (named after the Kehl family of ‘Kolane’, Wandoan,

Queensland Queensland ( , commonly abbreviated as Qld) is a States and territories of Australia, state in northeastern Australia, and is the second-largest and third-most populous state in Australia. It is bordered by the Northern Territory, South Austr ...

where the fossil was found).

Discovery

It is solely known from the

holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...

specimen, which consists of a nearly complete skull with mandible and postcrania were found within the Westgrove Ironstone Member of the

Evergreen Formation The Evergreen Formation is a Pliensbachian to Toarcian geologic formation of the Surat Basin in New South Wales and Queensland, eastern Australia. Traditionally it has been considered to be a unit whose age has been calculated in between the ...

of the

Surat Basin The Surat Basin is a geological basin in eastern Australia. It is part of the Great Artesian Basin drainage basin of Australia. The Surat Basin extends across an area of 270,000 square kilometres and the southern third of the basin occupies a larg ...

. Dating to the late

Toarcian The Toarcian is, in the International Commission on Stratigraphy, ICS' geologic timescale, an age (geology), age and stage (stratigraphy), stage in the Early Jurassic, Early or Lower Jurassic. It spans the time between 184.2 Megaannum, Ma (million ...

at approximately 176.6 ma. ''Siderops'' was large, with a

skull The skull, or cranium, is typically a bony enclosure around the brain of a vertebrate. In some fish, and amphibians, the skull is of cartilage. The skull is at the head end of the vertebrate. In the human, the skull comprises two prominent ...

width wide and a total length of .

Classification

''Siderops'' belongs to the clade

Brachyopomorpha Brachyopomorpha is a clade of stereospondyl temnospondyls within the infraorder Trematosauria. It was constructed in 2000 to include '' Bothriceps australis'' and the superfamily Brachyopoidea. It is phylogenetically defined as a stem-based ...

, a subdivision of the greater clade

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 ...

and placed in the superfamily

Brachyopoidea Brachyopoidea is a superfamily of temnospondyls that lived during the Mesozoic. It contains the families Brachyopidae and Chigutisauridae. The earliest records of brachyopids are from the Lower Triassic in Australia. The latest-surviving membe ...

and belonging in the

Chigutisauridae Chigutisauridae is an extinct family of large temnospondyls. The only genera recognized as belonging to Chigutisauridae at the current time are all from Gondwana. Chigutisaurids first appeared during the Early Triassic in Australia. During the ...

family. Shown below is a cladogram of Brachyopoidea adapted from ''Warren et al. (1983)'' and ''Ruta et al. (2007)''.

References

{{Taxonbar, from=Q784206 Jurassic temnospondyls Prehistoric amphibians of Australia Chigutisauridae Fossil taxa described in 1983 Early Jurassic amphibians Toarcian genera Jurassic animals of Australia Monotypic prehistoric amphibian genera