معرفی یک گونه جدید از جنس Deladenus (Hexatylina: Neotylenchidae) جدا شده از استان آذربایجان‌شرقی، شمال‌غرب ایران، با مطالعه ریخت‌شناسی و فیلوژنی مولکولی

A population of the genus Deladenus was recovered from a soil sample collected from Shursu region of Maragheh city, located in East Azerbaijan province. This species is mainly characterized by having a body length of (741-887 µm), pharynx 85-97 µm long with a long overlap of the dorsal gland overlapping intestine, small lateral vulva flaps and a conical tail with a relatively rounded tail, 33-38 µm long. In addition, the studied population has six lines in the lateral field, short stylet (6.5-7 µm), junction of pharynx with intestine on or before the nerve ring, excretory-secretory pore generally near or before the nerve ring. Its up to the hemizonid is 29-44 µm. The distance from the vulva to the anus 27.5-36 µm. Male was not found in this population. The vulva is located at about 90% of the body length and near to body end, postvulval uterine sac is absent. The characteristics of studied species were not in agreement with the currently known species of the genus and comes close with five species namely D. apopkaetus, D. cocophilus, D. durus, D. processus, D. persicus (having six or seven lines on the lateral field). In the molecular phylogenic analyses using ribosomal DNA sequences of small and large subunits of ribosome, the phylogenetic relationships of these two sequences with the sequences available in GenBank database were reconstructed using Bayesian approach and the resulted topologies were discussed.