پیشنهاد گونه‌ای از جنس Ektaphelenchus (Rhabditida: Ektaphelenchinae)، به عنوان گونه نهان Ektaphelenchus masseyi ، جمع ‏آوری شده از استان مازندران

Two populations of a tentative new species of Ektaphelenchus were recovered from natural forests of Tonekabon and Chalus cities of Mazandaran province, northern Iran. The new species is characterized by the lip region lacking a clear constriction separating it from the body contour, stylet relatively short (12.5-14.0 μm), without basal knobs, excretory pore anterior to, or at the metacorpus region, postuterine sac ca 1.5-2.1 body diam. long, anus and rectum indistinct in some individuals but vestigial in others, presumably not functional and posterior body end (tail) conical, ending to a rounded to pointed tip. Males are common and have 7-8 μm long spicules, seven caudal papillae, and a conoid tail with sharply pointed. The new species is morphologically compared with closely related species having conical posterior body ends and stylets lacking basal knobs or swellings. Considering a combination of morphological characters, e.g., stylet without basal knobs or swellings and similar posterior body end morphology, the new species comes close to eleven known species of the genus, namely: E. betulae, E. cupressi, E. ibericus, E. josephi, E. joyceae, E. kanzaki, E. masseyi, E. oleae, E. olitorius, E. prolobos and E. taiwanensis. The new species is morphologically closest to E. masseyi, forms its tentative cryptic species, showing remarkable nucleotide differences in two small and large subunit ribosomal RNA gene markers. The studied population was compared with species of the genus Ektaphelenchoides that have posterior body end (tail) short and conical, including: E. andrassyi, E. compsi, E. poinari and E. winteri. In Bayesian phylogenetic analyses using the SSU and LSU data, it formed a clade with E. masseyi. This is new evidence on cryptic speciation in nematodes indicating "apparently minor" morphological differences being corroborated with remarkable molecular differences.