First record of the genus Discotylenchus Siddiqi, 1980 (Nematoda: Tylenchidae) from Iran, with description of one and data on two known species

The genus Discotylenchus is reported for the first time from Iran. Discotylenchus iranicus n. sp. is described and illustrated based on morphological and morphometric characters. The new species is characterized by a combination of the following morphological features: lip region continuous and smooth, tapering to an offset prominent labial disc, lateral field with four incisures, stylet length of 14–15 µm, vulva position at 70.8–76.5 %, tail length of 81–100 µm, conoid with a rounded tip and presence of males. The Iranian population of D. brevicaudatus shows a wider morphometric range compared to the original description and the male of this species is described for the first time. The morphological characters and range of morphometric data of D. discretus are in full agreement with the original population.