Ottolenchus sinipersici n. sp. (Rhabditida: Tylenchidae) from the Persian Gulf mangrove forests, Iran

Abstract

Summary A new species of Tylenchidae from the rhizosphere of mangrove trees in Hormozgan and Khuzestan provinces, Iran, is described based on morphological and molecular data. Ottolenchus sinipersici n. sp., is characterised by a slightly fusiform body 560-665 μm long, lateral field in the form of a narrow band with two faint incisures that are not visible in fatter females, indistinct transverse annuli under the light microscope, cephalic region continuous with the body contour, smooth and flattened dorsoventrally, longitudinal and narrow sigmoid amphidial slits, stylet delicate, 10.1-11.2 μm long, with small rounded to slightly posteriorly sloping knobs, well-developed median bulb, offset and pyriform pharyngeal basal bulb, vulva located at 66.9-69.6% of body length, offset spermatheca, short post-vulval uterine sac, spicules 18.5-20.5 μm long with highly curved blades, and a 113-135 μm long filiform tail with a hook-like or coiled terminus. In Bayesian inference phylogenetic trees based on the partial small subunit ribosomal DNA (SSU rDNA) and D2-D3 expansion segment of large subunit ribosomal DNA (D2-D3 LSU rDNA) genes, the new species clustered together with O. facultativus (KJ869310) in SSU, and forms a clade with three isolates of O. discrepans in LSU phylogeny. Ottolenchus fungivorus n. comb. (= Filenchus fungivorus) is proposed.

Morphological and Molecular Characterization of Ottolenchus isfahanicus n. sp. (Tylenchomorpha: Tylenchoidea) from Rhizosphere of Gramineous Plants in Isfahan Province, Iran

“…The genus Ottolenchus is now a valid and well-established genus ( Qing and Bert, 2017 ; Hosseinvand et al, 2021 ). It is paraphyletic in SSU, and monophyletic in LSU phylogenies, after recent studies based on available sequences of its representatives ( Hosseinvand et al, 2021 ).…”

“…The genus Ottolenchus is now a valid and well-established genus ( Qing and Bert, 2017 ; Hosseinvand et al, 2021 ). It is paraphyletic in SSU, and monophyletic in LSU phylogenies, after recent studies based on available sequences of its representatives ( Hosseinvand et al, 2021 ). On the other hand, currently only few representatives of Ottolenchus have been sequenced and further information will better depict its phylogenetic nature in the future.…”

“…However, Siddiqi and Lal (1992) emphasized the characters differentiating Ottolenchus from Filenchus , and urged that Ottolenchus was a reliable taxon by virtue of the longitudinal, curved and sigmoid amphidial apertures, originating at the lateral lip areas and extending over most of the lip region, and narrow lateral field with two incisures. Siddiqi (2000) , Decraemer and Hunt (2006, 2013), Qing and Bert (2017) , and Hosseinvand et al (2021) also considered Ottolenchus to be a valid genus.…”