One of the rarest tetrapods in the East Kirkton fauna is an aïstopod represented by very fragmentary material of five individuals. It is described as a new species of the genus Ophiderpeton which is redefined and restricted to broad-snouted forms with large, robust teeth from the late Viséan and early Westphalian. Later Westphalian species are referred to the genus Oestocephalus.