A new species of the genus Aglenchus is described from the rhizosphere of a Montpellier maple tree in the Sepidar region, Kohgiluyeh and Boyer-Ahmad province, Iran. Aglenchus microstylus n. sp. is a small nematode characterized by the presence of three incisures in each lateral field, stylet of 7–8 µm length, short post-vulval uterine sac, lateral vulval flaps, straight vagina and elongated-conoid tail, with pointed to finely rounded terminus. The new species differs from all the known species of the genus, including more closely related A. dakotensis and A. geraerti, by having a short stylet (7-8 µm), a short post-vulval uterine sac and straight vagina. A modified key to identification of the species of genus Aglenchus is presented.
