Two new species of Onychiuridae (Collembola) from East Siberia (Russia)

Two new species of Onychiuridae (Collembola) from Buryatia (Russia, East Siberia), Supraphorura chernovae sp. nov. and Thalassaphorura transbaikalica sp. nov., are herein described and illustrated. Supraphorura chernovae sp. nov. differs from its closest species, S. furcifera (Borner, 1901), by its dorsal pso formula as 32/022/23232, presence of 1 pso on the subcoxae 1 of all legs, and a larger set of vesicles on the PAO. Thalassaphorura transbaikalica sp. nov. is most similar to T. tibiotarsalis Sun, Chen & Deharveng, 2010 by the same dorsal pso formula (32/233/33343) and presence of 7 chaetae on the distal whorl of all tibiotarsi, but differs from the latter species specially by the presence of 1 pso on the subcoxa 1 of leg 1 (T. tibiotarsalis has 2 pso), number of vesicles on the PAO (13-14 vs. 17-18), number of chaetae on the subcoxa 1 of legs 1-3 (4, 4, 4 vs. 3, 3, 3), and ratio of the empodial appendage and claw (0.8-0.9 vs. 0.5). After our study there are now 47 recorded species of Onychiuridae recorded from East Siberia.