''Plagiosuchus'' 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 ...

plagiosaurid Plagiosauridae is a clade of temnospondyl amphibians of the Middle to Late Triassic. Deposits of the group are most commonly found in non-marine aquatic depositional environments from central Europe and Greenland, but other remains have been foun ...

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 ...

. It is known from several collections from the

Middle Triassic In the geologic timescale, the Middle Triassic is the second of three epochs of the Triassic period or the middle of three series in which the Triassic system is divided in chronostratigraphy. The Middle Triassic spans the time between Ma and ...

of Germany.

History of study

The type and only species of ''Plagiosuchus, P. pustuliferus'', was originally described as a species of ''

Plagiosternum ''Plagiosternum'' (plae-jee-oh-ster-num, meaning "sideways breastbone") was a middle Triassic temnospondyl Temnospondyli (from Greek τέμνειν, ''temnein'' 'to cut' and σπόνδυλος, ''spondylos'' 'vertebra') is a diverse order o ...

'', with the specific epithet as pustuliferum''' by

Eberhard Fraas Eberhard Fraas (26 June 1862 – 6 March 1915) was a German scientist, geologist and paleontologist. He worked as a curator at the Stuttgarter Naturaliensammlung and discovered the dinosaurs of the Tendaguru formation in then German East Afri ...

in 1896. The interclavicle described and figured by Fraas had originally been noted by him as ''Labyrinthodon'' sp. in an 1889 publication and before that by von Meyer and Plienenger in a 1844 publication. This interclavicle was not formalized as the holotype but is recognized as the lectotype. The taxon was reassigned to the newly named genus ''Plagiosuchus'' in 1922 by von Huene, who described new material that permitted him to differentiate it from ''Plagiosternum granulosum''; this was also when the specific epithet was grammatically modified. Additional material was referenced and briefly figured by Hellrung (2003) and Werneburg and Witter (2005), but most of the osteology comes from the description of a complete skull, figured by Hellrung, by Damiani et al. (2009). Histology of the osteoderms and the limbs has also been analyzed.

Anatomy

''Plagiosuchus'' has a relatively long skull for a plagiosaurid, approximately as long as it is wide. However, its most defining feature is its greatly enlarged orbit, which forms a massive orbitotemporal fenestra with the loss of several post-orbital bones, including the postfrontal and the postorbital, and the reduction of several others. This fenestra is about 80% of the total length of the skull. The subtemporal vacuity on the palate is also correspondingly long, while the tooth rows are short, confined to the anterior portion of the skull. Ornamentation varies across the skeleton, with the distinct pustules found in many other plagiosaurids found on the pectoral elements, more typical temnospondyl ridging on the mandible, and more irregular large tubercles on the skull.

References

{{Taxonbar, from=Q7200535 Stereospondyls Fossil taxa described in 1922 Triassic temnospondyls of Europe Taxa named by Friedrich von Huene

History of study

Anatomy

See also

References