New sheath nematode, Hemicycliophora paraconida n. sp. (Rhabditida: Hemicycliophoridae) from Northern forest in Iran

Abstract

Hemicycliophora paraconida n. sp. from the Tilekenar forest in northern Iran, is described and illustrated. The new species is characterized by having female body length of 907–1197 µm, 286–341 body annuli and a 96–115 µm long stylet. Lateral fields with three longitudinal lines forming two rows of blocks with breaks and anastomosis of transverse striae; each annulus in lateral field with four subcuticular ovate markings. Tail elongated uniformly conoid, with distinct annuli and narrowly rounded to acute terminus. Male possess robust and semi-circular spicules and a well-developed penial tube. Based on molecular and morphological compari-sons, the new species comes close to seven species of the genus namely: H. conida, H. iwia, H. ovata, H. hellenica, H. poranga, H. ornamenta and H. halophila, but it differs from them by the body size, R related indices, stylet length, lateral field structure, vulva position and tail shape. Molecular analyses based on sequences of D2-D3 expansion segments of 28S rRNA gene supported its morphological status as a new species and revealed that the new species is closest to the H. conida clade in the dendrogram inferred using 28S D2-D3 gene.

Keywords

• 28S D2/D3
• Hemicycliophoroidea
• morphology
• morphometric
• new species
• taxonomy