Article: Upper Devonian tetrapods from Andreyevka, Tula region, Russia
Devonian tetrapod remains have been recovered from the Famennian of Russia. They occurred in a limestone with stromatolites, algae, numerous and diverse fish remains and the holotype of the tetrapod Tulerpeton curtum. The conditions indicate a shallow-water basin with carbonate-rich water and perhaps an estuarine or marine situation. The individual bones show some plesiomorphic similarities to those of other Devonian tetrapods and osteolepiform fishes, such as a high premaxillary tooth count, large fangs plus a marginal row of smaller teeth on the vomer, a low naris with unsutured premaxillary-maxillary junction, lack of shagreen on the coronoids and lateral line canals in tubes through the bone, but also share derived characters with some Carboniferous tetrapods, such as shagreen on the vomer, shape and suture pattern of supratemporal and intertemporal, and possession of a tabular horn. The findings indicate that tetrapods were already diverse by the Devonian, and that they may not have been confined to freshwater.