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520 FOSSIL VERTEBRATES/Mesozoic Amphibians and Other Non-Amniote Tetrapods Triassic Best known is the genus Micropholis (Figure 7), which is locally common in the Karoo of South Africa It is a late survivor of the Carboniferous– Permian family Amphibamidae, resembling long- legged salamanders and believed to be relatives of the modern amphibians by some workers The genus Tungussogyrinus from the Tungus Basin in Siberia is a tiny gill-bearing temnospondyl, first described as a larva but recently argued to be a late member of the Branchiosauridae, small paedomorphic temnospondyls best known from Permo–Carboniferous lake deposits in central Europe Finally the Tupilakosauridae known, from Greenland, Russia, and South Africa, were probably found throughout Pangaea and were long-bodied, almost eel-like, forms (Figure 8) Chroniosuchians Figure Skull of the brachyopid Batrachosuchus haughtoni, from the Middle Triassic, South Africa Specimen at the Natural History Museum, London ß Andrew Milner Anthracosaurs, a significant group of Carboniferous and Early Permian large carnivores, are widely believed to be stem-amniotes, i.e., amphibian-grade organisms closer to the origin of reptiles, birds, and mammals than to modern amphibians One relict anthracosaur taxon, the chroniosuchians, survived in the Late Permian of Russia (see Palaeozoic: End Permian Extinctions) They were small (50 cm–1 m) terrestrial carnivores superficially resembling monitor lizards Until the early 1990s, they were assumed to have been wiped out by the P–T event Recently, however, isolated characteristic armour-bearing vertebrae of chroniosuchians dating to the Middle Triassic have been found in Russia and Germany Post-Triassic Temnospondyls Figure An aggregation of five individuals of the temnospon dyl Micropholis stowii, from the Lower Triassic, South Africa Spe cimen at the Bayerische Staatsammlung fur Geologie und Palaontologie, Munich ß Andrew Milner Until 1977, it was generally assumed that all remaining temnospondyl lineages became extinct in the Norian during the extensive faunal turnover that occurred in the Late Triassic This still may be true for central and western Pangaea, but two families of aquatic temnospondyl survived in the eastern peripheries of the continent until much later The Brachyopidae are now known from the Middle–Upper Jurassic of Mongolia (Gobiops) and China (Sinobrachyops), and the similar Chigutisauridae have been described from the Lower Jurassic (Siderops; Figure 4B) and midCretaceous of Australia The latter record, Koolasuchus from the Aptian Stretzlecki Formation, is the latest known temnospondyl Figure Reconstruction of the temnospondyl Thabanchuia oomie, from the Lower Triassic, South Africa Reproduced with permission from Warren AA (1999) Karroo tupilskosaurid: a relict from Gondwana Transactions of the Royal Society of Edinburgh: Earth Sciences 89, 145 160
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