Morphological and molecular characterization of Ektaphelenchoides pini (Massey, 1966) Baujard, 1984 (Aphelenchoididae; Ektaphelenchinae) from Iran, with morphological and taxonomic observations on some species

Ektaphelenchoides pini, the type species of the genus Ektaphelenchoides, was recovered from wood and bark samples of a dead broadleaf forest tree collected from the forests of Golestan province in north of Iran. The recovered population is mainly characterized by massive wide spicules of males with well-developed condylus marked by indentations at the apex and simple distal tip. It was further characterized by 756 to 947 μm long females having a cephalic region slightly separated from the rest body by a shallow depression, 20 to 23 μm stylet with wide lumen lacking conophore and knobs, excretory pore (E pore) at about one metacorpus length behind it, or 92 to 106 μm from anterior end and hemizonid just posterior to it, vagina anteriorly inclined, post uterine sac (PUS) ca 1.2 times vulval body width long, posterior body region elongate conoid, ending to a filiform tip, no functional rectum, a vestigial anus and common males with dorsally convex tail ending to an elongate spike and two pairs of precloacal (P2) and caudal (P3) large papillae at 5 to 6 μm distance anterior to cloacal opening and 30 to 41% of tail, respectively and lacking the single precloacal papilla (P1). In molecular phylogenetic analyses using small and large subunit ribosomal DNA (SSU, LSU rDNA) sequences, the Iranian population of E. pini fell in a clade including species of three genera Ektaphelenchus, Ektaphelenchoides, and Devibursaphelenchus in SSU, and a clade including species of Ektaphelenchus and Ektaphelenchoides in LSU tree, in close association with an isolate identified as E. pini in the latter phylogeny with high (0.99) Bayesian posterior probability (BPP). The comparisons with the type and French populations, as well as phylogenetic affinities of the species using ribosomal data, are discussed. This is the first report of E. pini from Iran, and its first simultaneous morphological and molecular phylogenetic study. New observations on some species of the genus were also presented and discussed.