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 member of the superfamily is the chigutisaurid Koolasuchus from the Early Cretaceous of Australia.

Brachyopoidea Temporal range: Early Triassic - Early Cretaceous, 252.3–120 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Skull of the brachyopoid Pelorocephalus mendozensis
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Order:	†Temnospondyli
Suborder:	†Stereospondyli
Clade:	†Brachyopomorpha
Superfamily:	†Brachyopoidea Lydekker, 1885
Subgroups
See text.

Description

Restoration of the chigutisaurid Siderops kehli

Some large brachiopoids, such as Siderops and Koolasuchus, grew to lengths of around 2.5 metres (8.2 ft). However, an unnamed Late Triassic or Early Jurassic brachiopoid from Lesotho in southern Africa is estimated to have been far larger. At an estimated 7 metres (23 ft), the brachiopoid from Lesotho is one of the largest amphibians sensu lato^[a] ever known.[1] This estimate is based on a single jaw fragment found in 1970 by a French expedition near Alwynskop in Quthing.[2]

Because of its size, the fragment was initially considered to be from a mastodonsaur.[3] However, the specimen was redescribed as a brachyopoid in 2005. Several features of the specimen indicate that it is from a brachyopoid. There is a large tusk protruding from the ectopterygoid, a bone of the palate, and the dental morphology is similar to that of other brachyopoids. When viewed from the side, the upper margin of the jaw appears concave.[1]

Classification

Shown below is a cladogram of Brachyopoidea adapted from Ruta et al. (2007).[4]

Brachyopoidea	Brachyopidae      Sinobrachyops     Xenobrachyops         Banksiops     Batrachosaurus       Vanastega     Vigilius       Batrachosuchus        Chigutisauridae    Chigutisaurus         Compsocerops     Kuttycephalus         Pelorocephalus     Siderops

Notes

1. ^{^} Amphibians in the most general sense- i.e. terrestrial or semi-terrestrial vertebrates which do not belong to amniota.

References

1. Steyer, J.S.; Damiani, R. (2005). "A giant brachyopoid temnospondyl from the Upper Triassic or Lower Jurassic of Lesotho". Bulletin de la Société Géologique de France. 176 (3): 243–248. doi:10.2113/176.3.243.
2. Abrose, D. (2006). "Lesotho Palaeontology Updated". Summary of Events in Lesotho. 3 (1).
3. "Temnospondyli: Trematosauria (2): Rhytidosteids & Brachyopoids". Palaeos. Archived from the original on 4 January 2010. Retrieved 20 February 2010.
4. Ruta, M.; Pisani, D.; Lloyd, G. T.; Benton, M. J. (2007). "A supertree of Temnospondyli: cladogenetic patterns in the most species-rich group of early tetrapods". Proceedings of the Royal Society B. 274 (1629): 3087–3095. doi:10.1098/rspb.2007.1250. PMC 2293949. PMID 17925278.

General references

• Dong, Z. (1985). "The Dashanpu Dinosaur Fauna of Zigong Sichuan Short Report V - Labyrinthodont Amphibia". Vertebrata PalAsiatica. 23: 301–306.
• Marsicano, Claudia A. (2005) A new temnospondyl record from the Upper Triassic of Argentina. Ameghiniana, vol.42, no.2, p. 501-504. ISSN 0002-7014.
• Shishkin, M.A. (1991). "A Late Jurassic labyrinthodont from Mongolia". Paleontological Journal. 1991: 78–91.
• Warren, A. A.; Marsicano, C. (2000). "A phylogeny of Brachyopoidea (Temnospondyli, Stereospondyli)". Journal of Vertebrate Paleontology. 20 (3): 462–483. doi:10.1671/0272-4634(2000)020[0462:APOTBT]2.0.CO;2.
• Yates, A.M.; Warren, A.A. (2000). "The phylogeny of the 'higher' temnospondyls (Vertebrata: Choanata) and its implications for the monophyly and origins of the Sterospondyli". Zoological Journal of the Linnean Society. 128: 77–121. doi:10.1111/j.1096-3642.2000.tb00650.x.