Description of Scutylenchus quercinus n. sp. (Nematoda: Tylenchomorpha) from Asalem forests, north Iran

Abstract

Summary A new species of Scutylenchus was recovered from soil collected in the rhizosphere of forest trees in natural Asalem forests, Gilan province, north Iran. The new species is described and illustrated based upon morphological and molecular data. Scutylenchus quercinus n. sp. is mainly characterised by having four lines in the lateral fields, thus delimiting it from currently known species of the genus, which have six lines. It is further characterised by 605-709 μm long females having a slightly offset cephalic region with five or six annuli, stylet 19-21 μm long with conus ca 50% of its total length and three slightly posteriorly sloping knobs, vulva in a cavity, with epiptygma, vagina vera squarish in lateral view, female tail subcylindrical with smooth end, and males with 26-30 μm long spicules. The new species was morphologically compared with eight similar species. The molecular phylogenetic relationships of the new species with other relevant species and genera were reconstructed using partial small, large subunit and internal transcribed spacer ribosomal DNA (SSU, LSU D2-D3 and ITS1 rDNA) sequences and the resulting topologies were discussed.