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Two populations of the genus Trophotylenchulus and 10 species of the genus Paratylenchus from Iran were characterized based on morphometric, morphological and molecular characters. Our observations on the two populations of Trophotylenchulus from Iran revealed that T. asoensis and T. okamotoi have been distinguished from T. arenarius, on the basis of the features which cannot be longer considered as stable diagnostic characters. One of the populations shows a mixed combination of the characters of T. arenarius and T. asoensis; it has morphometrics more similar to T. arenarius but shows affinities with T. asoensis in the tail terminus shape of females and second-stage juveniles (J2) and in having a reduced stylet in males. The other population fit well with T. okamotoi; it has females with generally bluntly rounded tails typical for T. okamotoi, but sometimes with finely rounded tail termini, like those of T. arenarius or T. asoensis. The sequences of D2–D3 expansion segments of 28 S rRNA gene for the two populations are identical with each other, but only 4 bp (0.67%) difference with T. arenarius sequence deposited in the GenBank. Considering no stable difference allow separating species, synonymy of T. asoensis and T. okamotoi with T. arenarius, which has already been proposed, is supported and confirmed here. All studied Paratylenchus species with stylets longer than 40 µm, except P. straeleni, formed a basal cluster to Cacopaurus pestis and species of Paratylenchus bearing stylets shorter than 40 µm; thus, validity of Gracilacus cannot be rejected using our data sets. However, the synonymy of Paratylenchoides was supported by the positioning of P. sheri within representatives of Paratylenchus in the inferred phylogenetic tree.

Summary: A new species of the genus Talanema , T. maculatum sp. n., collected in a natural enclave of Iran, is characterised on the basis of morphological and molecular data. It is distinguishable by its 1.82-2.20 mm long body, lip region offset by constriction and 20-23 μ m wide with perioral liplets, odontostyle 21.5-28 μ m long, guiding ring double, neck 394-525 μ m long, pharyngeal expansion occupying 44-49% of the total neck length, uterus tripartite and 308-441 μ m long or 5.1-6.8 body diam., vulva transverse (V = 54-58), presence of abundant cuticle irregularities at the perivulval area, tail similar in both sexes, conical with a dorsal concavity (31-45 μ m, c = 46-71, c′ = 0.9-1.1), spicules 70-75 μ m long, and 14-18 shortly spaced ventromedian supplements ending at level of the anterior end of spicules, with hiatus. Molecular analysis of 28S-rDNA gene confirms the monophyly of Talanema and the difficulties in elucidating its external evolutionary relationships. [ABSTRACT FROM AUTHOR]

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 μ m 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 μ m 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 μ m long with highly curved blades, and a 113-135 μ m 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. [ABSTRACT FROM AUTHOR]

Summary: A new species of Coslenchus from north-western Iran is illustrated and described using morphological, morphometric and molecular data. Coslenchus persicus n. sp. is characterised by a medium-sized body of 694-810 μ m, often 18 (seldom 20-22) longitudinal ridges excluding lateral field, head with four distinct annuli, stylet 9.6-10.8 μ m long, pharyngeal basal bulb large and cylindrical, spermatheca offset and ovate, without sperm, vulval flaps extending for two annuli, 5-7 μ m in length, tail striated with finely to bluntly rounded tip, 110-153 μ m long and without males. The new species comes close to C. assamensis , C. diversus , C. japonicus , C. leiocephalus , C. maritus , C. multigyrus , C. paramaritus , C. pastor , and C. polonicus , but can be distinguished from all by differences in body length, stylet length and shape of basal bulb, post-vulval uterine sac, tail and certain morphometric data. Molecular data are provided for the characterisation of the new species using ribosomal genes (18S and 28S rRNA). In the 18S rRNA tree, the new species was placed in a clade including one isolate of Coslenchus sp. from Iran. In the reconstructed 28S rRNA phylogenetic tree, C. persicus n. sp. clustered with other known Coslenchus species. [ABSTRACT FROM AUTHOR]

Summary: Two new and one known species of Atetylenchus recovered from Dezful, Khuzestan Province, south-western Iran, are illustrated and described using morphological, morphometric and molecular data. Atetylenchus dezfuliensis n. sp. is characterised by medium-sized body 700-998 μ m long, stylet 10.0-11.5 μ m long, characteristic tail shape, first tapering regularly but then cylindrical to slightly clavate and 90-136 μ m long, phasmids located at one-third anterior part of tail and short spicules 18.7 μ m long. Atetylenchus longilabiatus n. sp. is characterised by small-sized body 593-720 μ m long, prominent lip region, stylet 9.5-12.5 μ m long, conical tail with hook-shaped terminus and 42-63 μ m long, phasmids located near mid-tail and short spicules 17.5 μ m long. Atetylenchus cf. graminus is characterised by small-sized body 643-787 μ m long, stylet 10.7-11.7 μ m long, vulva located at 51.7-55.1% of the body length, and conical tail with finely rounded end and 63-69 μ m long. Molecular data are provided for the characterisation of this genus from these two new and one known species using ribosomal genes (18S and 28S rRNA). This genus is molecularly separated from Psilenchus , but closely related in both genes. These molecular markers showed different phylogenies for both genera; partial 18S showed their relationship with Tylenchidae, while 28S rRNA showed their relationship with Merliniidae. A key to the genus is provided for species identification. [ABSTRACT FROM AUTHOR]

Summary: An undescribed species from the rhizosphere of tamarisk, Tamarix passerinoides , Telotylenchus tamariscus n. sp., is illustrated and described based on morphological, morphometric and molecular approaches. The new species is characterised by female characters including body size of ca 1 mm, areolated lateral fields, cephalic region rounded, distinctly set off from the body contour, stylet 19.5 (18.5-20.5) μ m long with posteriorly directed basal knobs, pharyngeal glands overlapping intestine dorso-laterally, subcylindrical tail bearing 32 (25-37) cuticular annuli and ending in an annulated terminus, and male spicules and gubernaculum 27 (25-29) and 13 (12.5-14.5) μ m long, respectively. Morphologically, our population comes close to several known species of the genus, including T. avaricus , T. aerolatus , T. indicus , T. ventralis , T. paaloofi and T. namibiensis. In the 18S rRNA phylogenetic tree, it occupied a phylogenetic position in close affinity with two sequences of T. ventralis. In the 28S rRNA tree, the genus Telotylenchus did not form a monophyletic group, our isolate clustering with an unknown population of Histotylenchus and four isolates of Tylenchorhynchus mediterraneus in a clade well separated from another clade that included three other isolates tentatively named as Telotylenchus sp. [ABSTRACT FROM AUTHOR]

Summary: In this study, we provide morphological and molecular characterisation of three known species of the Criconematoidea, namely Criconema cylindraceum , Paratylenchus alleni and P. steineri , recovered from Iran. Descriptions, morphometric data, drawings and photomicrographs are provided, and comparisons are made with closely related species. Phylogenetic analysis using the D2-D3 expansion segments of the 28S rRNA gene revealed that C. cylindraceum formed a cluster with Ogma decalineatus , a species with a similar head structure, but with differences in cuticle ornamentation, tail shape and morphometric characters. Moreover, P. alleni grouped with species of Paratylenchus having four lateral lines and a short stylet (< 40 μ m), exceptionally including the unresolved P. straeleni , while P. steineri formed a clade with long stylet species, including P. teres and P. wuae. The taxonomic placement of C. cylindraceum in Criconema , rather than in Criconemoides , is justified, and P. teres is molecularly differentiated from P. steineri , the two species differing in having or lacking a stylet in the fourth-stage juvenile. [ABSTRACT FROM AUTHOR]

During a nematological survey of the family Tripylidae, two new and two known species of the genus Tripyla, namely T. paraffinis sp. n., T. parafilicaudata sp. n., T. glomerans and T. setifera, were identified and described from soil samples collected from the rhizosphere of forest trees in northern Iran. Three populations of T. paraffinis sp. n., found in different locations, are described and morphometric data of the type and other populations provided. Tripyla paraffinis sp. n. is characterised by its body length of 1.21-1.89 mm, dorsal tooth wedge-shaped and triangular, short outer labial and cephalic sensilla, tail bent ventrad and gradually tapering to the end, horn-shaped spicules bearing a distinct constriction in the middle, and presence of 16-20 ventromedian supplementary papillae. Tripyla parafilicaudata sp. n. is described and illustrated from four different locations. It is characterised by females with a body length of 1.48-1.95 mm, dorsal tooth hook-shaped, vaginal wall with a downward pointing tooth-like projection in the middle, long outer labial and setiform cephalic sensilla, long tail, sausage-shaped spermatozoa, males with horn-shaped spicules and 11-17 ventromedian supplementary papillae. Tripyla glomerans and T. setifera are new records for the Iranian nematofauna. The results of phylogenetic analyses based on sequences of the partial 18S and D2-D3 expansion segments of 28S rRNA from T. paraffinis sp. n. and T. parafilicaudata sp. n. and other species in the genus clearly support the proposal of T. paraffinis sp. n. and T. parafilicaudata sp. n. as new species, as well as indicating that Tripyla shares a more recent common ancestor with Tobrilus, Tripylella, Prismatolaimus, Diphtherophora and two trichodorids, Trichodorus and Paratrichodorus. The Tripylidae is placed in a main clade within the Triplonchida. [ABSTRACT FROM AUTHOR]

A new bisexual species of Rotylenchus from North-western Iran is described and illustrated based on morphological, morphometric and molecular studies. Rotylenchus urmiaensis n. sp. is characterised by having a truncate lip region with irregular longitudinal striation, lateral field areolated only in pharynx region, stylet length 34-40 µm, vulva positioned at 53-61%, and female tail conoid-rounded to dorsally convex-conoid with 5-10 annuli. Rotylenchus urmiaensis n. sp. appears to be similar to R. striaticeps, from which it may be differentiated morphologically by a slightly shorter body length (870-1269 vs 1000-1723 µm), shorter stylet (34-40 vs 39-50 µm), female tail shape (conoid-rounded to dorsally convex-conoid vs rounded), frequency of males (rare vs common as abundant as females), shorter spicules (39-43 vs 41-50 µm) and phasmid position (varying from three annuli anterior or three annuli posterior to anus vs at level to seven annuli anterior to anus), and molecularly. The results of phylogenetic analyses based on sequences of D2-D3 expansion region of 28S, ITS-rDNA, 18S rDNA, and the partial cytochrome c oxidase subunit 1 (coxI) mtDNA, confirmed the species differentiation and the close molecular relationship between R. urmiaensis n. sp. and R. striaticeps. [ABSTRACT FROM AUTHOR]