Branchiosaurus

Not to be confused with the dinosaur Brachiosaurus.
Branchiosaurus
Temporal range: Lower Permian
B. salamandroides fossil
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Amphibia
Order: Temnospondyli
Suborder: Euskelia
Superfamily: Dissorophoidea
Family: Branchiosauridae
Genus: Branchiosaurus
Species

B. gracilis Credner, 1881
B. pusillus Frič, 1878
B. salamandroides Fritsch, 1875
B. umbrosus Fritsch, 1879

Branchiosaurus (Greek for "gill lizard") is a genus of small, lightly built early prehistoric amphibians. Fossils have been discovered in strata dating from the late Pennsylvanian Epoch to the Permian Period. The taxa may be invalid; the material referred to the genus may be juvenile specimens of larger amphibians.[1]

Restoration
Skeletal diagram

This tiny amphibian was very similar to the Rachitomi, differing primarily in size. Other distinguishing characteristics include a cartilaginous, less ossified skeleton and a shorter skull. Clear traces of gills are present in many fossilized samples, hence the name.

Originally thought to have vertebrae distinct from rachitomous vertebrae, it was placed in a separate order named Phyllospondyli ("leaf vertebrae"). Later analysis of growth stages showed increasing ossification in larger specimens, which showed that at lest some of the species was the larval stage of much larger rachitomes like Eryops, while others represent paedomorphic species which retained the larval gills in adulthood.[2]

Distribution is uncertain, though available fossils come from central Europe, most famous of which are the Permian Niederkirchen Beds around Pfalz, Germany.

References

  1. Andrew R. Milner, "The Tetrapod Assemblage from Nýrany, Czechoslovakia", in Systematics Association Special Volume No.15, "The Terrestrial Environment and the Origin of Land Vertebrates", ed. by A. L. Panchen, 1980, pp.439-496, Academic Press, London and New York
  2. Boy, J.A. (1972): Die Branchiosaurier (Amphibia) des saarpfalzichen Rotliegenden (Perm, SW-Deuchland). Abhandlungen des Hessische Landesamt, Bodenforschung No 65, pp 1-137

External links


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