Occurrence of Neodolichodorus persiangulfus n. sp. (Nematoda: Dolichodoridae) in mangrove forests of southern Iran

An infestation of mangrove forests with Neodolichodorus persiangulfus n. sp. in southern Iran is reported. This paper is the first to report a representative species of the genus in the country. The new species was characterized by 2,120 (1795-2400) mu m long females, and 1755 (1533-2019) mu m long males, a continuous to slightly offset cephalic region separated from the rest of the body by a shallow depression, having 5-7 annuli and a distinct labial plate, a lateral field with four lines, the outer ones crenate, irregularly areolated in anterior and posterior body region, 79 (66-85) mu m long female stylet, a didelphic-amphidelphic female reproductive system with asymmetric sclerotized vaginae, phasmids 5-10 annuli behind the anus, female tail elongate conoid, suddenly narrowing at 5-12 annuli posterior to anus and males with trilobed bursa, 52.5 (47-58) mu m long spicules and 21.5 (18-27) mu m gubernaculum. With the elongate-conoid female tail and cMODIFIER LETTER PRIME >1.2, the new species is close to five known species of the genus: N. brevistylus, N. leiocephalus, N. paralongicaudatus, N. rageshi and N. sinensis, but is distinguished from them by the morphology of the female tail, areolation type of the lateral field, position of hemizonid and phasmid and morphometric data. Molecular phylogenetic analyses using sequences of the near full-length fragment of the small and the D2-D3 expansion segments of the large subunit ribosomal DNA (SSU and LSU rDNA D2-D3) revealed the new species placed in a clade including one isolate of Neodolichodorus sp. and some species of Globodera, Heterodera and Rotylenchulus with 0.89 Bayesian posterior probability (BPP) in SSU phylogeny. The only available SSU sequence of the genus was the tentative closest relative to the new species in the inferred SSU tree. In the reconstructed LSU phylogenetic tree, N. persiangulfus n. sp. formed a poorly supported clade with Rotylenchulus spp. in Bayesian inference (BI), and the only other available D2-D3 sequence of the genus occupied a distant placement to the new species.