| abstract | A survey of eriophyoid mites on ferns was carried out in the Arasbaran forests, East Azerbaijan province, Iran. A new species of the genus Leipothrix Keifer (Eriophyidae: Phyllocoptinae: Phyllocoptini) was collected on Polypodium vulgare L. (Polypodiaceae), named as L. pterisfolii, described and illustrated. It is the first record of a mite of the tribe Phyllocoptini on a Polypodiaceae plant. This mite species was found also on a plant of the family Cystopteridaceae, namely Gymnocarpium dryopteris (L.) Newman, and this is the first record of an eriophyoid mite associated with a plant of this family, too. In addition, it is the first report of a fern-inhabiting eriophyoid mite in Iran. A key to the eriophyoid mite species collected on ferns worldwide and a table summarizing information on their type host, type locality and habitus are provided. |