Description of Deladenus tonekabonensis sp. n. from Iran with a key to species

Deladenus tonekabonensis sp. n. was isolated from dried wood of the Tree of Heaven (Ailanthus altissima) from the Sehezar forests in Tonekabon city in Mazandaran Province. The new species is characterised by a body length of 655 (561-777) and 592 (488-735) μm for mycetophagous females and males, respectively, a short stylet (7.5-8.8 μm) with three knobs backward. Lateral field with ten incisures, and an excretory pore toward the anterior part of the neck, located at 27.5 (22.0-35.5) and 28.0 (21.0-38.0) μm from the anterior end of the mycetophagous females and males, respectively. The distance of the excretory pore to the hemizonid is 66.0 (59.0-71.0) and 61.0 (57.0-67.5) μm for the mycetophagous females and males, respectively. Adults have a long overlapping dorsal pharyngeal gland, lacking a post-uterine sac (PUS), and in some specimens a very short post-uterine sac, 2.4-5.1 μm long, and a conical tail, narrowing towards the tail tip. Males are frequent with slender tylenchoid spicules and a leptoderan bursa reaching the tail tip. Molecular phylogenetic analyses based on 28S rDNA placed the new species close to Deladenus and Anguillonema species in a clade with 0.99 posterior probability support. The measurements, line illustration and light microphotographs are given for the new species.