Westlothiana lizziae is an early tetrapod. It is a transitional fossil, with a mixture of amphibian and early amniote characters.282 Its body shape had a superficial resemblance to modern-day lizards. It lived during the Carboniferous period, about 350 million years ago.
Temporal range: early Carboniferous
Smithson and Rolfe, 1990
Westlothiania in lifeEdit
The small size has made it a key fossil in the search for the earliest amniote, as amniote eggs are thought to have evolved in very small animals. There are derived (advanced) features which tie it in with the amniotes rather than amphibians. These are: unfused ankle bones, lack of labyrinthodont infolding of the dentine in teeth, a lack of an otic notch and a generally small skull.
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