Tulerpeton curtum (Lebedev 1984, Fammenian, Latest Devonian, 365 mya) was described as, “one of the first true tetrapods to have arisen.” Here it nests as the basalmost reptile, pushing Gephyostegus bohemicus back to the pre-amniotes. Very little other than the limbs are known. In life it would have been similar to and the size of Gephyrostegus, Urumqia and Eldeceeon. Tulerpeton lived in shallow marine waters.
The loss of the sixth digit
occurred more than once, just as the later loss of a fifth digit occurred more than once. We should look for taxa with six fingers at the base of the Reptilomorpha and Seymouriamorpha — unless Tulerpeton developed a sixth finger on its own.