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Nematode samplings in various areas and crops of Greece were carried out and the recovered nematode species were characterized using morphological and molecular data. Seven species of plant-parasitic nematodes were recovered, three of which are reported for the first time in Greece, including Hemicycliophora poranga, Helicotylenchus dihystera and Tylenchorhynchus zeae. Four other recovered species had already been reported in Greece, including Bitylenchus hispaniensis, Helicotylenchus microlobus, Nanidorus minor and Scutellonema brachyurus. D2–D3 segments of 28S rRNA gene for all of these nematode species are provided.

During a nematological survey in southern Iran, a population belonging to the family Tylenchidae was recovered from a tomato field in Bushehr province. The recovered population belongs to the genus Filenchus, was described and illustrated herein as F. multistriatus n. sp. It is mainly characterized by having a wide and low annulated lip region continuous with adjacent body; amphidial openings confined to the labial plate; four lines in lateral fields forming three bands, with the two outer bands broken by transverse, and the inner one broken by both transverse and longitudinal lines; and median bulb oval with visible valve and elongate-conoid tail uniformly and gradually narrowing toward the distal region, ending in a widely rounded tip. Its morphological and morphometric differences with three closely similar species were discussed. The phylogenetic relationships of the new species with other relevant genera and species were reconstructed using partial sequences of small, and large subunit ribosomal DNA (SSU and LSU rDNA) sequences. Morphometric and morphological data were also provided for an Iranian population of F. sandneri recovered from Bushehr province. Both populations were characterised using SEM data.

A new species from the family Tylenchidae was recovered in the grasslands of Isfahan province, Iran, and is herein described based on morphological and molecular data. Ottolenchus isfahanicus n. sp. is mainly characterized by having a faintly annulated cuticle; elongated, slightly sigmoid amphidial apertures developed metacorpus with distinct valve under LM; vulva located at 69.472.3% of body length; large spermatheca about 2.75 times of corresponding body width; and elongated conoid tail with broadly rounded tip. SEM observations showed that the lip region is smooth; the amphidial apertures are elongated, slightly sigmoid slits; and the lateral field is a simple band. It is further characterized by 477-to-515-μm-long females with delicate 5.7-to-6.9-μm-long stylets with small, slightly posteriorly sloping knobs, as well as functional males, in the population. The new species closely resembles O. facultativus, but is separated from it based on morphological and molecular data. It was further morphologically compared with O. discrepans, O. fungivorus, and O. sinipersici. The phylogenetic relationships of the new species with other relevant genera and species were reconstructed using near-full-length sequences of small subunit and D2-D3 expansion segments of large subunit (SSU and LSU D2-D3). In the inferred SSU phylogeny, the newly generated sequence of Ottolenchus isfahanicus n. sp. formed a clade with two sequences of O. sinipersici and sequences assigned to O. facultativus and O. fungivorus. In the inferred LSU phylogeny, the three newly generated sequences of the new species and LSU sequences of O. sinipersici and O. discrepans formed a clade.

Longidorid nematodes comprise more than 500 species, and Longidorus and Xiphinema are the most diversified, prevalent, and cosmopolitan genera within plant-parasitic nematodes. The genus Longidorus comprise a group of species, some of which are vectors of plant viruses. New sampling for needle nematodes was carried out in a grapevine area in Thessaloniki, northern Greece, and one nematode species of Longidorus (L. leptocephalus) was recovered. Nematodes were extracted from soil samples by modified sieving and a decanting method. Extracted specimens were processed using glycerol, mounted on permanent slides, and subsequently identified morphologically. Nematode DNA was extracted from individual, live specimens, and PCR (Polymerase Chain Reaction) assays were performed for D2-D3 expansion segments of 28S rRNA, ITS1 rRNA, and partial mitochondrial COI regions. Morphology and morphometric data obtained from this population were consistent with the original description and reported populations of L. leptocephalus. To our knowledge, this is the first report of L. leptocephalus in Greece and the second in the Mediterranean Basin after the record of the species from Slovenia, extending the geographical distribution of this species in Europe.

The nematode family Aphelenchoididiae is considered fungal-feeding, predatory, or root hair feeders. Some members of this family are universally present in agricultural landscapes and are an integral part of soil health and conservation studies. In the present soil nematode biodiversity survey, we detected four species of the genera Aphelenchus, Aphelenchoides, and Robustodorus. Because fungal-feeding nematodes from southern Alberta have not previously been reported, we conducted a detailed morphological and molecular investigation, identifying these species as Aphelenchus avenae, Aphelenchoides limberi, Aphelenchoides prairiensis n. sp. and Robustodorus paramegadorus n. sp. The first two species we document as new records from southern Alberta, whereas A. prairiensis n. sp. and R. paramegadorus n. sp. we describe in detail as new taxa. Briefly, A. prairiensis n. sp. is an amphimictic species having 4 lateral lines; hemispherical anteriorly flattened lip region; delicate stylet and swelling-like stylet knobs; excretory pore at the posterior edge of nerve ring. Female tail conical, gradually tapering towards a truncated end with single mucro. Spicule 23.0 (20.0–25.0) µm long having elongated rounded condylus, small, blunt conical rostrum, and lamina that gradually tapers towards the rounded distal end; three pairs of caudal papillae were present on the male tail. Robustodorus paramegadorus n. sp., is a parthenogenetic species with 3 lines in the lateral fields; lip region rounded, anteriorly flattened; stylet robust, with knobs rounded to bean-shaped; excretory pore located posterior to nerve ring; reproductive components were quite indiscernible with a short 24.0 (18.0–27.0) µm post-vulval uterine sac; tail conical, ending with pointed to wedge-shaped tip. We performed molecular characterizations for each species and constructed phylogenetic trees to study the phylogenetic relationship of these aphelenchid species. The discovery of A. prairiensis n. sp. and R. paramegadorus n. sp. indicates that soil nematode diversity is relatively unexplored in southern Alberta. The findings of this study will significantly enhance the identification processes and may contribute towards future soil health and biodiversity efforts. [ABSTRACT FROM AUTHOR]

A population of a species of dagger nematode (Xiphinema) belonging to the non-americanum group was recovered from the fields of kola nut (Cola sp.) in southern Nigeria. The morphological and morphometric data obtained from this population were consistent with the characteristics of the species Xiphinema ifacolum. In addition, molecular identification based on D2-D3 expansion segments of 28S rRNA and partial mitochondrial COI gene regions confirmed its identity. According to our knowledge, this is the first report of the species from Nigeria, and the second report from Africa, after the original description from Foulaya, Guinea.

Summary: A population of Xiphinema artemisiae was recovered from Iran, representing the first report after its original description from a meadow pasture in northern Caucasus, Russia. The Iranian population was recovered from the rhizosphere of grasses in the Damavand region, Tehran province. The females of the recovered populations are characterised by a lip region separated from the rest of body by a depression, a 5.1-5.6 mm long body, a 129-138 μ m long odontostyle, 76-85 μ m long odontophore, a uterus having a pseudo-Z-organ and crystalloid bodies observed in some specimens, and a short, rounded, dorsally more convex tail with a subcentral mucron, four juvenile developmental stages (the first stage was not recovered) and functional males. The Iranian population is morphologically and morphometrically similar to the type population and minor morphological differences can be attributed to geographical interpopulation differences. Molecular phylogenetic relationships of the Iranian population of X. artemisiae with other species were reconstructed using sequences of three genomic ribosomal markers, viz. small, large subunit D2-D3 and internal transcribed spacer (SSU, LSU D2-D3 and ITS) rDNA. [ABSTRACT FROM AUTHOR]

Summary: The study aims to provide the morphological and molecular characterisation of two newly discovered Cryptaphelenchus species, namely: C. curvatum n. sp. and C. tumidus n. sp. Morphologically both species are minute nematodes, possess medium-sized stylets with basal knobs laterally directed, and short post-uterine sacs (PUS). Cryptaphelenchus curvatum n. sp. was detected from the local Pinus branch samples and is characterised by having an equal proportion of adult males and females, medium-sized body lengths of females 353 (320-388) μ m and males 277 (256-293) μ m, lateral fields with four lateral lines, 8-10 μ m long stylet, PUS about one vulva body width long and conical posterior body end with a blunt pointed tip. Cryptaphelenchus tumidus n. sp. was detected in a packaging wood sample from Japan and is characterised by having rare male, short body lengths of females 236 (217-270) μ m and males 180 μ m, obscure lateral fields, stylet 6.8 (6.0-7.5) μ m, PUS about half vulva body width long and a slim conical posterior body end with a finely rounded tip. The phylogenetic trees were also constructed based on rRNA gene sequences (D2-D3 segments of the 28S, ITS and 18S) and discussed in detail. Since Cryptaphelenchus species offer multitrophic relationships among their insect vectors and associated microbiota, species recognition and molecular studies of recovered populations will facilitate researchers to determine whether these species might play any ecological roles in insect bionomics or the residing host tree. [ABSTRACT FROM AUTHOR]

The presence of plant-parasitic nematodes (PPNs) in cultivated areas is a limiting factor in achieving marketable crop yield. To control and alleviate the effects of these nematodes and determine appropriate management strategies, species-level identification is crucial. Therefore, we conducted a nematode diversity survey, which resulted in the detection of four Ditylenchus species in cultivated areas of southern Alberta, Canada. The recovered species had six lines in the lateral field, delicate stylets (>10 µm long), distinct postvulval uterine sacs, and pointed to rounded tail tips. The morphological and molecular characterization of these nematodes revealed their identity as D. anchilisposomus, D. clarus, D. tenuidens and D. valveus, all of which are members of the D. triformis group. All of the identified species were found to be new records in Canada except for D. valveus. Accurate Ditylenchus species identification is crucial because false-positive identification can result in the implementation of quarantine measures over the detected area. Our current study not only documented the presence of Ditylenchus species from southern Alberta, but also described their morpho-molecular characteristics and subsequent phylogenetic relationships with related species. The results of our study will aid in the decision on whether these species should become a part of nematode management programs since nontarget species can become pests due to changes in cropping patterns or climate. [ABSTRACT FROM AUTHOR]

Summary: Criconemoides neoinformis n. sp., a cryptic species of C. informis group, and C. persicus n. sp. were recovered from the rhizosphere of pear and grass, in Zanjan and West Azerbaijan provinces, northwestern Iran, respectively. Criconemoides neoinformis n. sp. is characterised by 522-585 μ m long females, having four separated pseudolips, anteriorly flattened lip region comprised of two annuli, 57-63 retrorse body annuli with smooth to slightly crenate margins, without anastomoses, 86.9-90.4 μ m long stylet, having 6-10 annuli from vulva to posterior end and tail conical rounded with two, three or multilobed terminus and presence of males. Criconemoides persicus n. sp. could be characterised by flatly rounded lip region, having fused rectangular pseudolips, 515-615 μ m body length, stylet 60-65 μ m, body annuli 120-132 with smooth to slightly crenate margins, without anastomoses, 9-12 annuli from vulva to posterior end and tail conical rounded with two trilobed terminus. In inferred phylogenies, these two new species clustered with known Criconemoides species in 18S, 28S, ITS and COI trees. These species are clearly separated molecularly by all the studied markers. The use of molecular markers, mainly D2-D3 expansion segments of 28S rRNA, ITS region and COI , are very promising in the case of cryptic species found in this group of nematodes. We provided molecular markers (two sequences per marker) for these new species with morphological/morphometrical data using an integrative taxonomy approach for the unequivocal identification of these species. [ABSTRACT FROM AUTHOR]

Members of the family Tylenchidae are highly abundant in soil habitats, including agricultural settings, where they play key ecological roles. In the present study, we identified three Tylenchidae species, namely Basiria bhabi, Coslenchus acceptus, and Filenchus vulgaris, using integrative taxonomy. The detailed morphological and morphometric characteristics, distribution, and host associations of each species were also discussed. Phylogenetic analyses of these populations with other Tylenchidae nematodes indicated the presence of divergent lineages in Filenchus and Basiria, whereas Coslenchus appeared to be a monophyletic genus. Herein, we aim to grow awareness about this common but least studied group of nematodes. The species reported in this study are new records for Canada, revealing that the identified nematode diversity in our cultivated areas is relatively underrepresented. Our analyses also provided greater taxonomic resolution and captured rare taxa that might have been missed or misidentified in prior nematode inventory surveys. These findings will add to our understanding of the nematofauna of southern Alberta, thereby providing a more complete picture of existing nematode diversity present in the fields of this highly cultivated region. [ABSTRACT FROM AUTHOR]

Summary: Specimens of a thin longidorid species collected in Peñalba (Huesca), north-west Spain, were previously described as Paralongidorus iberis. However, we conclude, through scanning electron microscopy and molecular studies on a population from about 15 km from the type locality and on paratype specimens, that this species was originally placed in the wrong genus. Both populations have pore-like amphidial apertures, not slit-like as in Paralongidorus , and the species is therefore transferred to Longidorus. Longidorus iberis n. comb. is regarded as a valid species and is clearly different from closely related species such as L. tabernensis , L. iliturgiensis , L. alvegus and L. indalus in morphometrics and molecular markers. Molecular data are reported for the first time, including the D2-D3 expansion segments of 28S rRNA, ITS1 rRNA, partial 18S rRNA and partial mitochondrial coxI regions. These molecular markers were used for inferring the phylogenetic relationships with other species within Longidorus and Paralongidorus , all clearly separating L. iberis n. comb. from other related taxa and placing the species in the Longidorus clade, rather than with Paralongidorus. [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: Sigmolenchus n. gen., is proposed as a new member of the Tylenchidae. The new genus is proposed based upon light and scanning electron microscopic (LM and SEM) observations and phylogenetic analyses based upon small, large and internal transcribed spacer sequences of ribosomal DNA (SSU, LSU D2-D3, ITS rDNA) and mitochondrial cytochrome c oxidase I gene (COI mtDNA) sequences. It is characterised partly by its slender body, but mainly by having a dorso-ventrally flattened, smooth and elevated cephalic region, unique elongate sinuous amphidial openings, each appearing as a wavy slit with three peaks, originating from the vicinity of the labial plate, extending posteriorly and reaching and passing the first body annulus, and a spacious amphidial fovea. It has an anteriorly rounded outline under LM, knobbed stylet, its conus comprising about one-third of the total length, lateral field with a single band, metacorpus with a distinct valve, vulva with small lateral flaps, and males common with tylenchoidiform spicules. The new genus is morphologically compared with seven tylenchid genera, viz., Chilenchus , Ecphyadophoroides , Filenchus , Labrys , Lelenchus , Sakia , and Tenunemellus , mainly by having small slender body and dorso-ventrally flat cephalic region, and is placed under the subfamily Ecphyadophorinae because of its slender body, elevated smooth cephalic region, long amphidial openings and spacious amphidial fovea. It was recovered from marine muddy sediments taken 2 m deep in mangrove forests off southern Iran. Currently S. sinuosus n. gen., n. sp. is monotypic. In SSU phylogeny, the new genus formed an unsupported sister relationship with Filenchus discrepans , and in LSU phylogeny it occupied a placement inside a major clade including several Tylenchinae genera. [ABSTRACT FROM AUTHOR]

The most prevalent dagger nematode recovered from rhizospheric soil samples of forest trees in the Afrātakhteh region of Golestan province (Iran) was Xiphinema afratakhtehnsis sp. nov. and it is described and illustrated with integrative approaches using both morphological and molecular criteria. It belongs to the morphospecies group 6 of the intragenic historical grouping of Xiphinema non-americanum species. The new species is characterized by females with 3.3–4.9 mm sized body, lip region separated from the rest of body by a depression, anteriorly expanded, 16–18 μm wide, vulva located at 47.2–58.5%, odontostyle 155–173 μm and odontophore 89–107 μm long, female genital system composed of two equally developed branches, the tubular part of each having spines, short symmetrically rounded female tail to symmetrically rounded with a small mucro-like projection at the end in a few females, rare males (n = 1 out of 74 females) with 83 μm long dorylaimoid spicules and four juvenile developmental stages. The third-stage juveniles (J3) have a characteristic tail shape (short, symmetrically conical with a club-shaped long mucro) demarcating the species, and being typologically useful for its separation from closely similar species (except X. cohni, with currently no data on its juvenile stages) viz. X. adenohystherum, X. iranicum, X. mazandaranense, X. nuragicum, X. pyrenaicum, X. robbinsi, X. sphaerocephalum and X. zagrosense. Molecular phylogenetic studies using genomic (partial large subunit and internal transcribed spacer 1 ribosomal RNA genes: D2-D3 and ITS1 rDNA) and mitochondrial cytochrome c oxidase subunit I gene (COI mtDNA) revealed the new species forming a unique lineage in all reconstructed trees using Bayesian inference (BI) and maximum likelihood (ML) methods. The sequenced isolates of the new species formed a monophyletic group in the D2-D3 tree. The sequenced isolates of the new species for their COI mtDNA formed four subclades in COI mtDNA phylogeny, and four haplotypes in corresponding analysis. [ABSTRACT FROM AUTHOR]

Summary: Populations of Hemicriconemoides chitwoodi , H. fujianensis , H. parasinensis , and Criconemoides myungsugae isolated in China from the rhizosphere soil of woody perennials were characterised molecularly, important morphological details being elucidated by SEM observations. The morphometric data of the Chinese populations were compared with all previously reported populations. The SEM observations of en face views indicated that H. chitwoodi and H. parasinensis have lip patterns belonging to type 1 and phylogenetically both species clustered with other Hemicriconemoides species that showed the same kind of lip pattern. On the other hand, H. fujianensis showed a lip pattern belonging to type 2 and phylogenetically appears basal to the above-mentioned clade. SEM observation of C. myungsugae showed that the first lip annulus forms a non-projecting uninterrupted disc and the labial annulus is a rectangular shape with slight dorsal and ventral indentations. Phylogenetic relationships among Criconemoides spp. are apparently not well resolved. The present study provides updated morphological descriptions, molecular diagnostics and phylogenetic relationships of H. chitwoodi , H. fujianensis , H. parasinensis , and C. myungsugae , the last species being the first report from China. [ABSTRACT FROM AUTHOR]

Three populations of Xiphinema non- americanum group species were detected in agricultural and natural ecosystems, during routine surveys for plant-parasitic nematodes in Spain. Based on morphological and molecular analyses, the species were identified as Xiphinema histriae and Xiphinema lapidosum, being this the first record and molecular characterization of both species in Spain. The morphometrics and morphology of the Spanish populations agree with those of the original description and paratype specimens and the present study provided a first description of the second to fourth juvenile stages of both species. A detailed study on the morphology in the Spanish populations of X. histriae, as well as in paratypes, showed a pseudo- Z-organ with weakly muscularized wall and containing numerous small dense granular bodies, which was different to the original description by Lamberti et al. (1993). This new finding suggests that X. histriae must be considered a member of the morphospecies Group 5 of X. non-americanum. Phylogenetic analysis based on D2 to D3 expansion segments of 28S gene, ITS1 and partial CoxI gene indicated that X. histriae and X. lapidosum are phylogenetically related with other Xiphinema non-americanum group spp. reported from Spain. Considering the pathological and economic importance of this group of nematodes, the combination of morphological characters, measurements, and molecular analysis is crucial for accurate identification of these species. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Longidorids are economically important plant-parasitic nematodes because several species are virus vectors. Populations of Paralongidorus sali and Longidorus jonesi, isolated from woody perennials of Hangzhou, Zhejiang, China, were characterized molecularly and morphologically. The morphometric data of the Chinese populations of both species were compared with other populations. The present study provided a first record of the occurrence of Paralongidorus in China coupled with description of the first-stage juvenile and male of L. jonesi. Phylogenetic analysis based on 18S and D2-D3 expansion segments of 28S gene indicated that L. jonesi clustered with L. jonesi reported from Japan and P. sali grouped with P. bikanerensis from Iran. Considering the pathological and economic importance of this group of nematodes, the study emphasized the need of updated descriptions from accurately identified specimens, isolation of sufficient material for examination, and molecular and phylogenetic analysis for a better understanding and diagnostics of Longidorid nematodes. [ABSTRACT FROM AUTHOR]

Root-knot nematodes of the genus Meloidogyne are recognised worldwide as a major production constraint in crops of primary economic importance. Knowledge of their diversity and prevalence, as well as the major environmental and agronomical cues for understanding their distribution in specific areas is of vital importance for designing control measures to reduce significant damage. We provide the first detailed information on the diversity, distribution and levels of Meloidogyne species infecting wild and cultivated olive soils in a wide-region in southern Spain that included 499 sampling sites. Overall Meloidogyne spp. were found in 6.6% of sampled olive plants, with 6.6% and 6.5% for cultivated and wild olive, respectively. We identified five previously described Meloidogyne spp. (Meloidogyne arenaria, M. baetica, M. hapla, M. incognita, M. javanica) and one new species (Meloidogyne oleae sp. nov.) which, characterized using integrative taxonomy, increases the known biodiversity of Meloidogyne spp. affecting olive. Meloidogyne arenaria and M. incognita were only found infecting cultivated olive varieties, while, M. baetica was only found infecting wild olive. Three major parameters drive the distribution of Meloidogyne spp. in cultivated olives in southern Spain, cover vegetation on alley, irrigation and soil texture, but different species respond differently to them. In particular the presence of M. incognita is highly correlated with sandy loamy soils, the presence of M. javanica with irrigated soils and cover vegetation, while the presence of M. arenaria is correlated with the absence of cover vegetation on alley and absence of irrigation. These parameters likely influence the selection of each particular Meloidogyne species from a major dispersal source, such as the rooted plantlets used to establish the orchards. [ABSTRACT FROM AUTHOR]

Sheathoid nematodes of the genus Hemicriconemoides are migratory root-ectoparasites of many crops but damage is documented for only a few species. Hemicriconemoides paracamelliae sp. n., isolated in Hangzhou, Zhejiang, China, from the rhizosphere of Cinninghamia lanceolata, is described together with H. kanayaensis and H. parataiwanensis. These three species are characterised morphologically and molecularly with important morphological details elucidated by SEM photographs. The new species can be characterised by the en face view having a dorsoventrally orientated oral disc with slit-like opening, and the labial plate being composed of two lateral semi-globular shaped projections on the lateral sides of the oral disc. This new species has the first lip annulus expanded and slightly wider than the second, stylet 83 (80-85) µm long, excretory pore located 5-6 annuli posterior to the base of the pharyngeal bulb, vulva slit-like, vulval flaps absent, spermatheca rounded to oblong-shaped, and anus located 5-8 annuli posterior to vulva. The tail is elongated, conoid, with the terminal annuli curving dorsally or ventrally to form a finely rounded tip. The study provides the first record of H. kanayaensis from mainland China, a new host association of H. parataiwanensis, and molecular sequencing data of the 18S, 28S D2-D3 and ITS sequences. [ABSTRACT FROM AUTHOR]

A new and a known longidorid nematode, Paralongidorus lusitanicus n. sp. and Paralongidorus plesioepimikis, are described and illustrated from populations extracted from soil associated with grapevine (Vitis vinifera L.) from Escaroupim and Pó (central-Western Portugal), respectively. The new needle nematode P. lusitanicus n. sp. is characterised by a very large body size (8072-12,022 μm), an expanded and rounded lip region, ca 30 μm wide, with a clear constriction followed by a depression posterior to the amphidial aperture, amphidial fovea very large (11.0-19.0 μm), stirrup-shaped, with conspicuous slit-like aperture as shown in scanning electron microscopy studies, a very long and flexible odontostyle (180.0-223.0 μm), guiding ring located at 28.0-41.5 μm from anterior end, vulva anterior to the mid-body (34-41%), a dorsally convex-conoid tail with rounded terminus (29-42 μm long), bearing two or three pairs of caudal pores and males common (ratio 1:1.6 females) with spicules ca 80 μm long. Morphological and morphometric traits for P. plesioepimikis fit well with the original description, and is reported for the first time in Portugal. Integrative diagnosis of both species was completed with molecular data obtained using D2-D3 expansion segments of 28S rDNA, ITS1-rDNA and partial 18S-rDNA. The phylogenetic relationships of these species with other Paralongidorus spp. using these three molecular markers indicated that P. lusitanicus n. sp. clustered together with other Paralongidorus spp. forming a sister clade with P. plesioepimikis, both of them sharing a large body, long odontostyle, an anteriorly located vulva and an expanded and rounded lip region with a clear constriction followed by a depression posterior to the amphidial aperture. [ABSTRACT FROM AUTHOR]

Hemicycliophora presently contains 132 valid species of sheath nematodes. Within several samples obtained from surveys in Canada, South Africa, Spain and the USA, we distinguished six valid and six putative unidentified species by integrating the results of morphological and molecular analyses. Valid species included: H. californica, H. gracilis, H. parvana, H. poranga, H. raskii, and H. signata. The putative unidentified species were indicated as Hemicycliophora sp. 10, sp. 12, sp. 15, sp. 16, sp. 17, and sp. 18. Two new species of sheath nematodes from Spain and the USA were described and named as H. onubensis sp. n. and H. robbinsi sp. n., respectively. Hemicycliophora wyei is proposed as a junior synonym of H. parvana and H. ripa is proposed as a junior synonym of H. poranga. Eighteen valid and 13 unidentified species of sheath nematodes were characterised using the partial COI mtDNA gene. A total of 94 new sequences of which 77 were for the COI mtDNA gene were obtained in this study. Phylogenetic relationships within Hemicycliophora, using the D2-D3 expansion segments of 28S rDNA, ITS rRNA and COI gene sequences, are presented as inferred from Bayesian analysis. [ABSTRACT FROM AUTHOR]

A new dagger nematode, Xiphinema poasense n. sp., is described and illustrated from three populations extracted from soil associated with a combined plantation of Eucalyptus sp., Cupressus sp. and Pennisetum sp. and wild plants from a tropical premontane forest in Costa Rica. The new dagger nematode is characterised by a moderate body size 2612 (2416-3042) µm long, a rounded lip region 15.0 (13.5-16.5) µm broad, separated from the body contour by a shallow depression, amphidial fovea large, stirrupshaped, a very long odontostyle (175 (164-188) µm), stylet guiding ring located 167 (136-181) µm from anterior end, vulva situated anterior to mid-body (36-40%), anterior genital branch complete but strongly reduced, without uterine differentiation, female tail short, hemispherical to convex-conoid with a c' ratio = 0.7 (0.6-0.8) and bearing two pairs of caudal pores, and male absent. 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). The phylogenetic relationships based on D2-D3 segments of this species with other Xiphinema spp. of the X. non-americanum group indicated that X. poasense n. sp. clustered with other species with a reduced anterior genital branch from the morphospecies Group 2, viz., X. costaricense and X. krugi. However, the phylogeny of coxI and partial 18S rRNA gene revealed that the new species did not cluster with Xiphinema species having the anterior genital branch absent or reduced (i.e., morphospecies Groups 1 and 2, respectively). [ABSTRACT FROM AUTHOR]