''Stegotretus'' 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 ...

microsaur Microsauria is an extinct, possibly polyphyletic order of tetrapods from the late Carboniferous and early Permian periods. It is the most diverse and species-rich group of lepospondyls. Recently, Microsauria has been considered paraphyletic, as s ...

referred to the

Pantylidae Pantylidae is an extinct family of tetrapods of the group Recumbirostra. It also often considered a phylogeny, sister-group to the family Tuditanidae. The family contains two genera ''Pantylus'' and ''Stegotretus'', while a third, ''Sparodus'', ...

. It is known from the

Carboniferous The Carboniferous ( ) is a Geologic time scale, geologic period and System (stratigraphy), system of the Paleozoic era (geology), era that spans 60 million years, from the end of the Devonian Period Ma (million years ago) to the beginning of the ...

–

Permian The Permian ( ) is a geologic period and System (stratigraphy), stratigraphic system which spans 47 million years, from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.902 Mya. It is the s ...

boundary

Cutler Formation The Cutler Formation or Cutler Group is a stratigraphic unit exposed across the U.S. states of Arizona, northwest New Mexico, southeast Utah and southwest Colorado. It was laid down in the Early Permian during the Wolfcampian epoch. Desc ...

exposures of

New Mexico New Mexico is a state in the Southwestern United States, Southwestern region of the United States. It is one of the Mountain States of the southern Rocky Mountains, sharing the Four Corners region with Utah, Colorado, and Arizona. It also ...

History of study

Material now referred to ''Stegotretus'' was first described (in brief) by Eberth & Berman (1983). It was formally named by Berman et al. (1988). The genus name comes from the Greek ''stegos'' ('roof') and ''tretos'' ('perforated') to refer to a large fenestra found on the

palatine A palatine or palatinus (Latin; : ''palatini''; cf. derivative spellings below) is a high-level official attached to imperial or royal courts in Europe since Roman Empire, Roman times.

bone. The species name, ''S. agyrus'', is said to be derived from Greek ''agyrus'' ('gathering' / 'crowd') in reference to the concentration of all known specimens in a small area. The proper word in ancient Greek for 'gathering' / 'crowd' is however ''agora'' (ἀγορά), with the variant ''agyris'' (ἄγυρις) in the

Aeolic In linguistics, Aeolic Greek (), also known as Aeolian (), Lesbian or Lesbic dialect, is the set of dialects of Ancient Greek spoken mainly in Boeotia; in Thessaly; in the Aegean island of Lesbos; and in the Greek colonies of Aeolis in Anat ...

dialect.Liddell, H.G. & Scott, R. (1940). ''A Greek-English Lexicon. Revised and augmented throughout by Sir Henry Stuart Jones with the assistance of Roderick McKenzie.''Oxford: Clarendon Press. The holotype and referred materials are currently reposited in the

Carnegie Museum of Natural History The Carnegie Museum of Natural History (abbreviated as CMNH) is a natural history museum in the Oakland (Pittsburgh), Oakland neighborhood of Pittsburgh, Pennsylvania. It was founded by List of people from the Pittsburgh metropolitan area, Pit ...

. A large number of partial to complete skulls and associated postcrania are known for this taxon.

Anatomy

Despite the large number of specimens of ''Stegotretus'', many are poorly preserved or distorted. ''Stegotretus'' is diagnosed by the presence of only two premaxillary teeth and by a large circular fenestra on the palatine. A contact between the maxilla and the quadratojugal and the absence of an entepicondylar foramen on the humerus separate it from the purportedly closely related ''

Pantylus ''Pantylus'' (from , 'all' and , 'knob') is an extinct microsaurian tetrapod from the Permian period of North America. ''Pantylus'' was probably a largely terrestrial animal, judging from its well-built legs. It was about long, and resembled ...

''.

Relationships

''Stegotretus'' was classified as a pantylid by Berman et al. (1988). This has been validated by phylogenetic analyses that include the taxon, although it is sometimes recovered as being more closely related to '' Sparodus'' than to ''Pantylus'' when all three taxa are sampled. Below is the result of the analysis by Huttenlocker et al. (2013):

References

{{Taxonbar, from=Q7606720 Microsauria Pennsylvanian tetrapods of North America Cisuralian tetrapods of North America Fossil taxa described in 1988