New record of three species of Ditylenchus Filipjev, 1936 (Nematoda: Anguinidae), with a key to the species reported from Iran

Fifteen species of the genus Ditylenchus were recovered and identified from Kermanshah province, western Iran. Morphological and morphometric characters of three known species namely D. filimus, D. hexaglyphus and D. nanus, being new records for Iran’s nematode fauna, are given and discussed. Ditylenchus filimus is characterized by having a short stylet (7-8 µm), four lines in lateral fields, well-developed and valvate median bulb, and the typical female tail ending to a filamentous process. D. hexaglyphus, is characterized by having a short stylet (6.5-8.0 µm), six lines in lateral fields, not developed and non-valvate median bulb, and conoid tail with rounded tip. D. nanus, is characterised by having a short stylet (6-7 µm), six lines in lateral fields, median bulb well-developed and valvate, and tail conoid with finely rounded tip. A dichotomous key for identification of the species occurring in Iran is also provided.