Members of superfamily Raphignathoidea are important biological control agents of spider mites, eriophyid mites, and scale insects in agriculture and forestry. They were found in various ecosystems: foliage, branches, trunks, moss and lichen, litter, soil, animal nests, stored products, and even in house dust. Family Stigmaeidae is the largest family within Raphignathoidea, which was established by Oudemans (1931). This family currently contains 32 genera, of which 12 genera are recorded from Iran (Bayzavi et al., 2013). Currently the family Cryptognathidae contains the genera CryptognathusKramer, 1879; FavognathusLuxton, 1973; and CryptofavognathusDoğan & Dönel, 2010. Cryptognathuscomprises 19 species recorded from the Palaearctic, Nearctic and Australian regions and Favognathushas 33 species and occurs all over the world except the Antarctic region (Khanjani et al., 2014). During 2013-2014, fauna of the families Cryptognathidae and Stigmaeidae associated with oak trees in Nahavand were studied. In this order, litter and soil samples were taken to the laboratory. Mites extracted by Berlese funnel and mounted directly in Hoyer’s medium. In total 9 species belonging to 3 genera were identified. Zetzelia kamalihad high population on oak trees. Identified species are listed as follow: Eustigmaeus dogani Khanjani et. al., 2011; Eustigmaeus ioanninensis Kapaxidi & Papadoulis 1999;Eustigmaeus sculptus Doğan & Fan, 2003;Eustigmaeus segnis (Koch, 1836);Stigmaeus shendabadiensis Haddad Irani-Nejad & Lotfollahi, 2010;Zetzellia kamalii Kheradmand & Fathipour, 2007;Favognathus miraziiKhanjani & Ueckermann, 2008; Favognathus alvandiiKhanjnai et al., 2014; Favognathus guilanicus Khanjnai et al., 2014.
