Paralongidorus rex was found for the first time in Poland and Ukraine. This paper describes females and juveniles from four populations of this species on the basis of morphology and morphometrics and provides molecular characterization using 18S, ITS1 and D2-D3 expansion segments of 28S rRNA gene sequences. Morphometrically, females from these populations differed slighty in V ratio (means in four populations: 41.9; 42.7; 46.1; 46.8) and odontostylet length (166.6; 170.6; 191.5; 193.2). Phylogenetic analysis showed that P. rex had a sister relationship with P. iranicus. PCR-D2-D3 of 28S-RFLP diagnostic profiles with five enzymes are given. Additionally, information on new host plants and map of distribution for P. rex are provided. The new record of this nematode species, previously identified as Paralongidorus sp.

Summary Females and juveniles from a population of Xiphinema ifacolum from Sri Lanka are described based on morphology, morphometrics and molecular analyses. Morphologically, females and juveniles from Sri Lanka are similar to original descriptions and other reports from Brazil, Cameroon, Liberia, and São Tomé and Príncipe. The identity of the species was also confirmed by 18S rRNA gene sequences deposited in NCBI from Brazil (AY297826). Integrative diagnosis was completed with molecular data using D2-D3 expansion segments of 28S rRNA, ITS1 region, partial 18S-rRNA and the partial mitochondrial gene cytochrome c oxidase subunit 1 (coxI). This is the third molecular characterisation for a species of the X. non-americanum Group 4, after X. oleae and X. tica. The use of different ribosomal and mitochondrial markers in this study, particularly, D2-D3, ITS1 and partial coxI, provided a precise and unequivocal tool for the identification of X. ifacolum and contributes to a better knowledge of the diversity within Xiphinema. Morphospecies Group 4 appears to be a paraphyletic group within the X. non-americanum assemblage.

Seven needle nematode species of the genus Longidorus have been reported in Ukraine. Nematological surveys for needle nematodes were carried out in Ukraine between 2016 and 2017 and two nematode species of Longidorus (L. caespiticola and L. poessneckensis) were collected from natural and anthropogenically altered habitats on the territory of Opillia and Zakarpattia in Ukraine. Nematodes were extracted from 500 cm 3 of soil by modified sieving and decanting method. Extracted specimens were processed to glycerol and mounted on permanent slides and subsequently identified morphologically and molecularly. Nematode DNA was extracted from single individuals and PCR assays were conducted as previously described for D2-D3 expansion segments of 28S rRNA. Sequence alignments for D2-D3 from L. caespiticola showed 97%-99% similarity to other sequences of L. caespiticola deposited in GenBank from Belgium, Bulgaria, Czech Republic, Russia, Slovenia, and Scotland. Similarly, D2-D3 sequence alignments from L. poessneckensis, showed 99% to other sequences of L. poessneckensis deposited in GenBank from Slovakia and Czech Republic. Morphology, morphometry, and molecular data obtained from these samples were consistent with L. caespiticola and L. poessneckensis identification. To our knowledge, these are the first reports of L. caespiticola and L. poessneckensis in Ukraine, extending the geographical distribution of these species.

The family Longidoridae Thorne, 1935 is a big taxon of Dorylaimina sub-family. Its species are ectoparasites of vascular plants inhabiting terrestrial biotopes. Longidoridae is one of the most homogeneous groups of Dorylaimina, which differs distinctly in morphology and biology from other dorylaimids, but its representatives structurally and ecologically are very similar to each other. Seventeen species of this family belonging to three genera were previously reported from the territory of Ukraine. This paper presents first record of Longidorus intermedius Kozlowska & Seinhorst, 1979 and new records of closely related species Longidorus elongatus (de Man, 1876) Thorne & Swanger, 1936 from Ukraine. Data on morphology, morphometrics and main differences between Ukrainian populations of these two species are provided. Ukrainian populations of L. intermedius are also compared in details with other previously reported populations of this species, and main differences are described. The presence of only three juvenile deve lopmental stages in L. intermedius was confirmed. In model natural and anthropogenically altered localities on the territory of Opillia, the host preference of L. intermedius and L. elongatus was analyzed in detail. On this territory, L. intermedius is closely associated with Quercus robur L., so it can be used as an indicator for natural and semi-natural forests in which oak associations represent a primary vegetation type. On the contrary, L. elongatus populations were reported from the rhizosphere of a wide range of host plants. According to its chorological characters, L. intermedius can be also used in phylogeographical research in order to determine the formation ways of nemoral complexes of soil organisms after the Last Glacial Maximum.

Summary Genus Longidorus Micoletzky, 1927 consists of obligatory plant root ectoparasites. Some of the genus species are of economic importance as pests of agricultural plants. This paper presents first records of Longidorus attenuatus Hooper, 1961 and L. danuvii Barsi et al., 2007 from Ukraine. Data on morphometrics and D2-D3 28S rDNA region sequence are provided. Additionally, a D2-D3 28S rDNA sequence from a population described previously from Poland was included. For the first time L. danuvii has been found with plants of agricultural importance (Malus domestica Borkh., Pyrus sp. and Rubus idaeus L.). Additionally, this nematode species has been found for the first time in localities with relatively dry conditions (on the tops of the hills), which are distant from banks of rivers – biotopes from which it has been recorded previously.