گزارش یک گونه جدید از جنس Epidorylaimus Andrassy 1986 از استان کردستان

The genus Epidorylaimus, resembles Eudorylaimus in having a conoid tail, but differs from this genus with regard to a comparatively more slender-longer body, much longer (4–8 times the anal body diameters) tail and absence of hiatus in males. In this study, in order to identify the fauna of nematodes, several soil samples were collected from the rhizosphere of Walnut trees in Kordestan province during 2015 and 2016. Nematodes were extracted using the modified whitehead method, fixed by De Grisse method and transferred to anhydrous glycerin. After the preparation of permanent slides, identification of nematodes was performed based on morphological and morphometrical characteristics and using a light microscope equipped with a drawing tube and valid identification keys. Molecular and phylogenetic analysis were also performed for confirmation of the identification accuracy. After the DNA extraction, D2-D3 segment of 28S rRNA gene was amplified and the resulting amplicons were sequenced. The phylogenetic tree was generated using Mrbayes software. Based on morphometrical and morphological data the studied population was identified as Epidorylaimus sp. It is characterized by having a relatively slender (a= 28-37), 1.07-1.28 mm long body, female genital system amphidelphic, vulva transverse, located in the middle of the body, lip region set-off by constriction, 11-14 μm wide, odontostyle 15-16.5 μm long, aperture occupying 25 to 32% of the odontostyle length, odontophore 24 μm long, neck length 281-328 μm, rectum 25-30 μm long, spicules 32 μm long, with 5-7 ventromedian supplements, tail elongate conoid (76-97 μm), ventrally arcuate, with a hyaline occupying 32 to 41% tail length. Despite the original description of the genus, the understudy population having a hiatus. The female of Epidorylaimu sp differs from E. andrassyi in having, shorter tail (76-99 vs 100-116 μm), longer odontophore (24 vs 18.5-22.5 μm), longer neck length (281-328 vs 258-280 μm), greater c (11.7-13 vs 8.7-11.1) and V (45-51 vs 38.5-41) values. The molecular analysis confirmed the results obtained by morphological and morphometrical studies, and three identical populations of the species formed a single clade adjacent to E. lugdunensis, but differs from the latter species in its body length, c, c` values and spicules length.