Description of Rotylenchus arasbaranensis n. sp. from Iran with discussion on the taxonomic status of Plesiorotylenchus Vovlas, Castillo & Lamberti, 1993 (Nematoda: Hoplolaimidae)

Rotylenchus arasbaranensis n. sp., a new monosexual species is described and illustrated based on morphological, morphometric and molecular studies. The new species is characterised by having an offset and hemispherical lip region with 5-6 annuli, 32-36 μm long stylet, vulva located at 43.9-59.2% with a single epiptygma and rounded tail, rarely bilobed, with 6-8 annuli. The species R. striaticeps and the male of R. buxophilus are reported for the first time from Iran and R. fragaricus is reported and studied for the second time after its original description. The results of the phylogenetic analyses based on the sequences of the D2- D3 expansion region of the 28S, ITS1-rRNA and the partial 18S rRNA genes were provided for the studied species, confirming their differences from each other and determining the position of them and their relationships with closely related taxa. Also, the validity of Plesiorotylenchus is discussed on the basis of molecular data and its synonymisation (with only one sequence) with Rotylenchus is accepted.The first four authors acknowledge the Iranian National Science Foundation (INSF) and Tarbiat Modares University (Iran) for the financial support; while the sixth to eighth authors acknowledge the financial support by grant AGR-136 from ‘Consejería de Economía, Innvovación y Ciencia’ from Junta de Andalucía, and Union Europea, Fondo Europeo de Desarrollo regional, ‘Una manera de hacer Europa’. SEM pictures were obtained with the assistance of technical staff and the equipment of ‘Centro de Instrumentación Científico-Técnica (CICT)’, University of Jaén.Peer Reviewe