Basilaphelenchus hyrcanus n. sp. (Rhabditida: Tylaphelenchinae) associated with bark of a beech tree (Fagus orientalis Lipsky) from northern Iran.

Basilaphelenchus hyrcanus n. sp., the sixth species of the newly established genus was isolated during a nematode survey associated with bark samples of beech tree in northern Iran, which differs from the other species by body size, stylet length, metacorpus structure, and tail characters of both genders. The new species is also characterized by elevated cephalic region with sclerotised vestibule, posteriorly directed stylet knobs, well-developed metacorpus filling corresponding body region, position of excretory pore at the level of base of metacarpus, length of post uterine sac by 38-60 µm long, conoid elongate tail by sharp to finely rounded tip in female. Based upon the morphological characteristics and phylogenetic analyses of partial 18 S and D2-D3 28 S rDNA segments, the new species mostly resembles B. magnabulbus. However, B. hyrcanus n. sp. is clearly different from this species by having a longer stylet, different position of the excretory pore, a different male tail tip characters and 4.4 and 13.2% sequence divergences in 18 S and D2-D3 28 S, respectively.

Description of Tylencholaimus discus sp. n. (Nematoda, Dorylaimida, Tylencholaimidae) from Iran.

A new species of the genus Tylencholaimus, collected in natural areas of Iran, is described and illustrated, including SEM observations. Tylencholaimus discus sp. n. is characterized by its 0.65-0.76 mm long body, lip region offset by weak constriction and 7-7.5 µm broad with a conspicuous perioral disc, odontostyle 6-7 µm long, odontophore 9-10.5 µm long and visibly flanged rather than knobbed, neck 230-259 µm long with anterior region weakly muscular and basal expansion 98-125 µm long or occupying 42-49% of total neck length, female genital system mono-prodelphic, posterior branch reduced to a uterine sac 2-20 µm long or much shorter (0.1-0.6 times) than body diameter but very occasionally consisting of uterus, sphincter and a small terminal mass all together measuring 35-40 µm long, V = 65-74, tail short and rounded (13-17 µm, c = 41-57, c' = 0.6-0.8), and male unknown.

Description of Aphelenchoides macrospica n. sp. (Nematoda: Aphelenchoididae) from Northwestern Iran.

Aphelenchoides macrospica n. sp. is described and illustrated from the West Azerbayjan province, northwestern Iran. The new species is characterized by its body length of 807 to 963 µm (males) and 792 to 1,094 µm (females), offset cephalic region, lateral fields with four incisures, long stylet with 15 to 16 µm length, and excretory pore situated opposite or behind the nerve ring. Pharyngeal glands overlapping intestine dorsally and extending for 90 to 121 µm, tail terminus mucronate in both sexes. Vagina directed anteriad, and spicules are relatively large (27-32 µm) with well-developed broadly rounded apex and condylus. The new species comes close to seven known species of the genus namely A. arcticus, A. blastophthorus, A. haguei, A. huntensis, A. lucknowensis, A. parasaprophilus, and A. xui, but it differs from them by the body size, stylet length, size of spicules, and length of postvulval uterine sac. The results of phylogenetic analyses based on sequences of D2-D3 expansion region of 28S and 18S rDNA, confirmed its status as a new species.

Rotylenchus sardashtensis n. sp., a monosexual species from Iran, with molecular identification and detailed morphological observations on an Iranian population of Rotylenchus cypriensis Antoniou, 1980 (Nematoda: Rhabditida: Hoplolaimidae).

Rotylenchus sardashtensis n. sp., a new monosexual species is described and illustrated based on morphological, morphometric and molecular studies. Rotylenchus sardashtensis n. sp. appears close morphologically and molecularly to eight known species of the genus, i.e. R. buxophilus Golden, 1956, R. eximius Siddiqi, 1964, R. breviglans Sher, 1965, R. cypriensis Antoniou, 1980, R. pakistanensis Maqbool & Shahina, 1986, R. vitis Cantalapiedra-Navarrete, Liébanas, Archidona-Yuste, Palomares-Rius & Castillo, 2012, R. paravitis Cantalapiedra-Navarrete, Navas-Cortés, Liébanas, Vovlas, Subbotin, Palomares-Rius & Castillo, 2013 and R. dalikhaniensis Aliramaji, Pourjam, Álvarez-Ortega, Pedram & Atighi, 2015 from which the morphological differences are discussed. The new species is characterised mainly in having a hemispherical and well set off lip region with 3-4 annuli under light microscopy and irregular cob-like appearance under scanning electron microscopy (SEM), a stylet 26-30 µm long, a vulva located at 61-77% of body length with double epiptygma, rounded tail with 2-4 annuli and ventral mucron at its tip. Morphologically, R. sardashtensis n. sp. could be distinguished from all similar species within the genus by its matrix code as follows: A3, B1, C1, D4, E1, F2, G2, H5, I2, J2, K1. Rotylenchus cypriensis collected from the rhizosphere of Prunus sp. in Gilangharb region is characterised with its morphological and molecular data. Phylogenetic analyses based on sequences of the D2-D3 expansion region of the 28S rRNA gene and the ITS1 fragment revealed the relationships of both species examined in present study and other species of the genus Rotylenchus Filipjev, 1936 and the family Hoplolaimidae Filipjev, 1934 included in analyses.