Criconematidae (Nematoda) from oak forests in two nature reserves in Russia.

Seven criconematid species: Ogma menzeli, Criconema annuliferum, C. princeps, Criconemoides pleriannulatus, Mesocriconema solivagum, M. xenoplax and Xenocriconemella macrodora were recovered from soil samples collected from oak forests in the Shulgan-Tash and Voronezh nature reserves in Russia. Examination of C. pleriannulatus by SEM confirmed the absence of submedian lobes and revealed the presence of a small lip annule; juveniles exhibit fringe-like cuticular ornamentation of the annules. Ogma menzeli and C. pleriannulatus are new geographical records for Russia, and all species have already been reported in association with different oak species with the exception of M. solivagum and C. pleriannulatus. Criconemoides mutabilis Eroshenko, 1980 is proposed as ajunior synonym of C. pleriannulatus Ebsary, 1979.