Background and Objectives The accurate identification of taxons especially species and genera is very important for a better understanding of biology, ecology, life cycle and other aspects such as pathogenicity. Materials and Methods In order to identify plant parasitic nematodes associated with oak trees of Khoramabad city, Iran, 82 soil and foliar samples of oak trees were collected from different regions of Khoramabad city, during 2014 and 2015. After extraction, killing and fixation of nematodes, identification of species was carried out considering morphological and morphometrical characters using a digital camera equipped light microscope. Results In this study, 26 nematodes species From Tylenchomorpha infraorder and Longidoridae family including: Aphelenchus avenae,Laimaphelenchus australis L. penardi, Paraphelenchus amblyurus,Aprutides guidetti, Ditylenchus medicaginis, D. anchilisposomus,D. parvus,Mesocriconema antipolitanum,Amplimerlinius globigerus, Scutylenchus rugosus, Merlinius brevidens, M. nanus,Trophurus ussuriensis, Helicotylenchus digonicus, H. exallus, H. vulgaris, Pratylenchoides ritteri, Pratylenchus neglectus, P. thornei, Zygotylenchus guevarai, Boleodorus thylactus,Discotylenchus sp, Psilenchus hilarulus, Paratylenchus similis, and Xiphinema index were identified.
Among the identified nematodes, 19 species are reported for the first time from oak tree in Iran. Laimaphelenchus australis is characterized by ventrally arcuate body; cephalic region set off; four incisures in lateral field; vulva without a flap, post-uterine sac extending for about one-third the vulva-anus distance, tail conoid with a single stalk-like terminus and four pedunculate tubercles.L. penardi male nematodes by are morphology similar to that of female, 12.9-13.1 μm long stylet, 25.2-26.0 μm long spicule, testis outstretched, spermatocytes in a single column, spicules paired, rosethorn–shaped, with prominent capitulum and rostrum broad with bluntly rounded tip. L. australis and male of L. penardiare new records for the nematofauna of Iran. These fungal nematodes are likely to affect the balance of endophytic fungi populations on oak trees, indicating the importance of identifying these nematodes, and D. anchilisposomus is re-described herein.