In the present study, the mitochondrial DNA phylogeny of five solifuge families of Iran is presentedusing phylogenetic analysis of mitochondrial cytochrome c oxidase, subunit 1 (COI) sequence data. Moreover, we included available representatives from seven families from GenBank to examine the genetic distance between Old and New World taxa and test the phylogenetic relationships among more solifuge families. Phylogenetic relationships were reconstructed based on the two most probabilistic methods, Maximum Likelihood (ML) and Bayesian inference (BI) approaches. Resulting topologies demonstrated the monophyly of the families Daesiidae, Eremobatidae, Galeodidae, Karschiidae and Rhagodidae, whereas the monophyly of the families Ammotrechidae and Gylippidae was not supported. Also, within the family Eremobatidae, the subfamilies Eremobatinae and Therobatinae and the genus Hemerotrecha were paraphyletic or polyphyletic. According to the resulted topologies, the taxonomic placements of Trichotoma michaelseni (Gylippidae) and Nothopuga sp. 1 (Ammotrechidae) are still remain under question and their revision might be appropriate. According to the results of this study, within the family Galeodidae, the validity of the genus Galeodopsis is supported, while the validity of the genus Paragaleodes still remains uncertain. Moreover, our results revealed that the species Galeodes bacillatus, and Rhagodes melanochaetus are junior synonyms of G. caspius, and R. eylandti, respectively
