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Encyclopedia of geology, five volume set, volume 1 5 (encyclopedia of geology series) ( PDFDrive ) 1108

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FOSSIL VERTEBRATES/Palaeozoic Non-Amniote Tetrapods 473 Figure Diagram to show the distribution in time of some Late Palaeozoic tetrapod groups, with one view of their relationships Romer’s Gap is shown as a shaded band, and this time period probably represents that during which these major groups diversified Representative animals are shown on some of the branches, but these are not to scale Baphetid skulls, such as Megalocephalus figured here, reached over 300 mm in length Balanerpeton, shown representing temnospondyls, grew to a total body length of between 300 and 400 mm The embolomere, Pholiderpeton, shown representing anthracosaurs, probably reached a length of over m Casineria was about the size of a mouse, and Westlothiana that of a small lizard The microsaur, Pelodosotis, featured here was only about 30 mm in length, but others grew to around 300 mm Keraterpeton, representing the nectrideans, reached about 300 mm in total, although later ones grew much larger (see Figure 8) The aıstopod, Lethiscus, seen here had a skull length of about 30 mm, but the full length of its body is not known Arrows show that the group or its descendants survived to the present day T, Tournaisian; V, Vise´an; N, Namurian; W, Westphalian; S, Stephanian In the later Vise´ an, three localities, all near Edinburgh, Scotland, have yielded significant tetrapod specimens Two, close in both time and space, have each yielded a single but intriguing specimen, while the third has yielded a whole flora and fauna of terrestrial organisms Casineria kiddi (Figure 5), from Cheese Bay on the Firth of Forth, is the earliest fully terrestrial tetrapod known It is small, unusual in such an early tetrapod, and has a clearly pentadactyl hind foot that could grasp the substrate Despite the specimen not preserving a head, this animal appears to be the earliest representative of the amniote stem

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