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Summary A revised characterisation of the dorylaimid nematode Paraxonchium carmenae is provided, including an updated description, SEM observations and molecular (18S-, 28S-rDNA) analyses. A total of 29 females and 16 males, collected from several mountain natural locations in eastern Andalusia, Spain, are studied. This species is very homogeneous morphologically, but displays wide variations in their morphometrics, although with high coincidence or overlapping when the ranges of different populations are compared. The morphology of the genus Paraxonchium is analysed and discussed, with emphasis on its remarkable interspecific variations. Results of molecular studies show a close relationship of P. carmenae with P. laetificans, the type species of the genus, and tentatively support its monophyly. Nevertheless, neither morphological nor molecular data clear up the uncertainties about its position in the Dorylaimina system.

Summary A new root-knot nematode, parasitizing Robusta coffee in Dak Lak Province, Western Highlands of Vietnam, is described as Meloidogyne moensi n. sp. Morphological and molecular analyses demonstrated that this species differs clearly from other previously described root-knot nematodes. Morphologically, the new species is characterized by a swollen body of females with a small posterior protuberance that elongated from ovoid to saccate; perineal patterns with smooth striae, continuous and low dorsal arch; lateral lines marked as a faint space or linear depression at junction of the dorsal and ventral striate; distinct phasmids; perivulval region free of striae; visible and wide tail terminus surrounding by concentric circles of striae; medial lips of females in dumbbell-shaped and slightly raised above lateral lips; female stylet is normally straight with posteriorly sloping stylet knobs; lip region of second stage juvenile (J2) is not annulated; medial lips and labial disc of J2 formed dumbbell shape; lateral lips are large and triangular; tail of J2 is conoid with rounded unstriated tail tip; distinct phasmids and hyaline; dilated rectum. Meloidogyne moensi n. sp. is most similar to M. africana, M. ottersoni by prominent posterior protuberance. Results of molecular analysis of rDNA sequences including the D2–D3 expansion regions of 28S rDNA, COI, and partial COII/16S rRNA of mitochondrial DNA support for the new species status.

This article belongs to the Special Issue Plant Parasitic Nematodes., Root-lesion nematode species rank third only to root-knot and cyst nematodes as having the greatest economic impact on crops worldwide. A survey of plant-parasitic nematodes associated with decaying raspberries (Rubus sp.) in northern Italy revealed that root-lesion nematodes were the most frequently occurring species among other phytonematodes. Several Pratylenchus species have been associated with Rubus sp. in Canada (Quebec, British Columbia) and USA (North Carolina, Maryland, New Jersey) including P. penetrans and P. crenatus. In the roots and rhizosphere of symptomatic raspberries, nematodes of two Pratylenchus spp. were detected. Detailed morphometrics of the two root-lesion nematode isolates were consistent with Pratylenchus crenatus and with an undescribed Pratylenchus species. The extracted nematodes were observed and measured as live and fixed materials and subsequently identified by integrative taxonomy (morphometrically and molecularly). The latter species is described herein as Pratylenchus vovlasi sp. nov., resulting morphometrically closest to P. mediterraneus and phylogenetically to P. pratensis. The molecular identification of Pratylenchus vovlasi sp. nov. was carried out by sequencing the ITS region, D2-D3 expansion domains of the 28S rRNA gene and a partial region of the nuclear hsp90 gene. ITS-RFLP and sequence analyses revealed that Pratylenchus vovlasi sp. nov. had species-specific restriction profiles with no corresponding sequences present in the database. The phylogenetic relationships with ITS and D2-D3 sequences placed the Pratylenchus vovlasi sp. nov. in a clade with P. pratensis and P. pseudopratensis. This research confirms the occurrence of cryptic biodiversity within the genus Pratylenchus as well as the need for an integrative approach to the identification of Pratylenchus species., F.D.L. acknowledges the Piedmont region through project NEMVIR/302/2010.

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., The first author is a recipient of a contract from the Ministry of Science and Innovation for Predoctoral Researchers in Spain, PRE2019-090206.

This article belongs to the Special Issue The Systematics, Morphological, and Molecular Characterization of Economically Important Plant–Parasitic Nematodes., Dagger nematodes of the genus Xiphinema include a remarkable group of invertebrates of the phylum Nematoda comprising ectoparasitic animals of many wild and cultivated plants. Damage is caused by direct feeding on root cells and by vectoring nepoviruses that cause diseases on several crops. Precise identification of Xiphinema species is critical for launching appropriate control measures. We deciphered the cryptic diversity of the Xiphinema hispanum-species complex applying integrative taxonomical approaches that allowed us to verify a paradigmatic example of the morphostatic speciation and the description of a new species, Xiphinema malaka sp. nov. Detailed morphological, morphometrical, multivariate and genetic studies were carried out, and mitochondrial and nuclear haploweb analyses were used for species delimitation of this group. The new species belongs to morphospecies Group 5 from the Xiphinema nonamericanum-group species. D2-D3, ITS1, partial 18S, and partial coxI regions were used for inferring the phylogenetic relationships of X. malaka sp. nov. with other species within the genus Xiphinema. Molecular analyses showed a clear species differentiation not paralleled in morphology and morphometry, reflecting a clear morphostatic speciation. These results support the hypothesis that the biodiversity of dagger nematodes in southern Europe is greater than previously assumed., This research was supported by Spanish Ministry of Science, Innovation and Universities, grant number RTI2018-095345-B-C21, LITHOFOR (“Modulating role of LITHOlogy in the response of Mediterranean FORest ecosystems to climate change: growth, edaphological processes and future predictions”) and the Humboldt Research Fellowship for Postdoctoral Researchers awarded for the first author.

The root-knot nematode speciesMeloidogyne daklakensisn. sp. was discovered on the roots of Robusta coffee (Coffea canephoraPierre ex A. Froehner) in Dak Lak Province, Vietnam. This species is characterized by the females having rounded or oval perineal patterns, smooth, regular, continuous striae, and reduced lateral lines. The dorsal arch is low, rounded and encloses a quite distinct vulva and tail tip. The stylet is normally straight with well-developed and posteriorly sloped knobs. The males have a rounded cap that extends posteriorly into the lip region. The procorpus is outlined distinctly, and is three times longer than the metacorpus. The metacorpus is ovoid, with a strong valve apparatus. The species closely resemblesM. marylandi,M. naasi, M. ovalis, M. panyuensis, M. lopezi, M. maliandM. baeticain the perineal pattern of the females, and the morphology of the males and the second-stage juveniles. Nonetheless, it can be differentiated from other species by a combination of morphometric, morphological and molecular characteristics. Phylogenetic analysis was conducted based on the internal transcribed spacer (ITS) and 28S rDNA as well as the region between the cytochromecoxidase I (COI) and cytochromecoxidase II (COII) mitochondrial genes. Herein, this nematode is described, illustrated, and designated as a new species,Meloidogyne daklakensissp. n., based on morphometric, morphological and molecular analyses.

Here, we describe under scanning electron microscopy (SEM) the morphology of Colpocephalum pectinatum (Phthiraptera, Menoponidae), an ectoparasite found in burrowing owls, Athene cunicularia. We devote particular attention to the morphology of the main structures of the head (antennae and mouth-parts) and legs (tarsi and femoral ctenidia). Moreover, we describe the main peripheral sensory organs, located in the labial palpi and the distal end of antennae. We also detected that the structure of antennae and antennal sensilla arrangement are very similar to that described for other Colpocephalum and Menoponid species, and we discuss the function of each type of sensilla. We suggest that SEM studies combined with other microscopy and physiological techniques could be useful for elucidate the function of each structure, lice behaviour, as well as their taxonomy. Junta de Andalucia (RNM-118; RNM-182) University of Jaen (PAIUJA 2021/2022: EI_RNM02_ 2021) 2.075 Q2 JCR 2021 0.670 Q1 SJR 2021 No data IDR 2021 UEM

A new species of the genus Geocenamus was isolated from soil and root samples from the rhizosphere of Casuarina equisetifolia (Casuarinaceae) in Quang Nam province, Vietnam. This species is characterized by a round-to-hexagonal labial disc, the presence of a labial region, which is continuous or slightly offset from the body with six sectors, lateral sectors of first labial annulus being smaller than the submedian sectors, the presence of six to seven labial annules; the absence of deirids; stylet length 24 to 28 μ m long, body length 776 to 979 μ m long; lateral field with six to eight lateral lines, without areolation at mid-body and with areolation in outer bands at the tail region and a pointed tail terminus. Geocenamus vietnamensis n. sp. most closely resembles G. boghiae in having a non-sclerotized head framework and lacking a bursa in the males. It can be clearly distinguished from all other species of the genus Geocenamus by these characteristics. The combination of morphology, morphometric features, and phylogenetic trees, based on D2-D3 of 28S and ITS rDNA sequences, showed that this new species can be clearly separated from all other sequenced species. This record is the first for Geocenamus in Vietnam. A new species of the genus Geocenamus was isolated from soil and root samples from the rhizosphere of Casuarina equisetifolia (Casuarinaceae) in Quang Nam province, Vietnam. This species is characterized by a round-to-hexagonal labial disc, the presence of a labial region, which is continuous or slightly offset from the body with six sectors, lateral sectors of first labial annulus being smaller than the submedian sectors, the presence of six to seven labial annules; the absence of deirids; stylet length 24 to 28 μ m long, body length 776 to 979 μ m long; lateral field with six to eight lateral lines, without areolation at mid-body and with areolation in outer bands at the tail region and a pointed tail terminus. Geocenamus vietnamensis n. sp. most closely resembles G. boghiae in having a non-sclerotized head framework and lacking a bursa in the males. It can be clearly distinguished from all other species of the genus Geocenamus by these characteristics. The combination of morphology, morphometric features, and phylogenetic trees, based on D2–D3 of 28S and ITS rDNA sequences, showed that this new species can be clearly separated from all other sequenced species. This record is the first for Geocenamus in Vietnam.

Discopersicus iranicus n. gen., n. comb., previously described from Iran as a new species under the genus Discotylenchus, is illustrated using light microscope and scanning electron microscope (SEM) observations and further studied using molecular characters. SEM studies revealed the newly proposed genus has oblique amphidial apertures on the lateral sides of the lip region. SEM images are also provided for two species of Discotylenchus, namely D. discretus and D. brevicaudatus, as the first SEM study of the genus. These results confirmed longitudinal amphidial aperture type on lateral sides of the lip region in genus Discotylenchus, as noted by Siddiqi while erecting the genus with D. discretus as the type species. Molecular phylogenetic analyses using partial small subunit (SSU) and large subunit (LSU) rDNA sequences revealed the affinity of the genus Discopersicus n. gen. with members of the subfamily Boleodorinae, as supported by morphological characters (mainly, the oblique amphidial opening).

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., This work was supported by Project P12-AGR-1486 from the `Consejería de Economía, Innovación y Ciencia' of Junta de Andalucía to PC, the grant 219262 ArimNET_ERANET FP7 2012-2015 Project PESTOLIVE `Contribution of olive history for the management of soilborne parasites in the Mediterranean basin' from the Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA) to PC, Project AGL-2012-37521 from the `Ministerio de Economía y Competitividad' of Spain, FEDER financial support from the European Union, and grant 201740E042 “Análisis de diversidad molecular, barcoding, y relaciones filogenéticas de nematodos fitoparásitos en cultivos mediterráneos” from the Spanish National Research Council (CSIC) to PC.

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., The sixth author thanks financial support from grant 201740E042, ‘Análisis de diversidad molecular, barcoding, y relaciones filogenéticas de nematodos fitoparásitos en cultivos mediterráneos’ from the Spanish National Research Council (CSIC).

This research carried out an accurate identification of the root-knot and cyst-forming nematode species parasitizing white clover at the Laceno Lake area in Southern Italy. Two species, the root-knot nematode Meloidogyne hapla and the cyst nematode Heterodera daverti were identified by integrative taxonomic approaches (classical, isozyme pattern, and D2-D3 expansion segments of 28S rRNA, ITS rRNA and coxI of mtDNA gene sequences) and found parasitizing white clover roots. These nematodes were detected in stunted plants with a reduced number of rhizobium nodules and the host suitability was confirmed by the high nematode population densities ranging from 53 to 2350 eggs and J2s per g of fresh roots for M. hapla, and 1.36 eggs and J2s/cm3 of soil for H. daverti; and cyst nematode females were also detected on the roots of clover. The studies on the host-parasite relationships of nematode-feeding sites in white clover roots infected by these nematodes showed a high susceptible response. Meloidogyne hapla and H. daverti infections were also observed on nitrogen-fixing root nodules of white clover, where well established feeding sites allowed active nematode reproduction. Histological examination of nitrogen-fixing root nodule tissues revealed that the nematodes established their permanent feeding sites in the vascular bundles of nodules which appeared enlarged deformed and disorganised by the expansion of nematode feeding cells (giant cells and syncytium) and hyperplasia of the nodule cortex. Additionally, coxI of mtDNA gene is an efficient barcoding sequence for discriminating the identification of H. daverti from H. trifolii., The present work has been done in the frame of the Apulia Region Programme: Misura 214/4 sub azione a “Progetti integrati per la Biodiversità” PSR 2007–2013, ASSE II “Miglioramento dell’ ambiente e dello Spazio Rurale” SaVeGraINPuglia.

The identity and evolutionary relationships of the genus Rhyssocolpus are analysed and discussed using an integrative approach including morphological data and partial SSU-rDNA sequences. An Iberian population of R. iuventutis is characterised in detail, providing the first SEM observations of the genus. New sequences of the genera Enchodelus and Rhyssocolpus are provided for comparative purposes. Both morphological and molecular evidence support a separate status for the aforementioned two genera and Heterodorus, of which the latter and Rhyssocolpus shared a recent common ancestor, whereas Enchodelus did not, as had been traditionally assumed, occupy a close position. The Nordiidae is confirmed to be an artificial taxon. The taxonomy of Rhyssocolpus is revised and an emended diagnosis, updated list of species, key to their identification and compendium of their morphometrics are provided. Some nomenclatorial changes are also proposed: R. alleni and R. paradoxus are retained under Eudorylaimus, their original genus, whereas R. brasiliensis is transferred to Eudorylaimus as E. brasiliensis (Meyl, 1956) comb. n.

A new bisexual species of Rotylenchusfrom North-western Iran is described and illustrated based on morphological, morphometric and molecular studies. Rotylenchus urmiaensisn. 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 urmiaensisn. sp. appears to be similar to R. striaticeps, from which it may be differentiated morphologically by a slightly shorter body length (870-1269 vs1000-1723 μm), shorter stylet (34-40 vs39-50 μm), female tail shape (conoid-rounded to dorsally convex-conoid vsrounded), frequency of males (rare vscommon as abundant as females), shorter spicules (39-43 vs41-50 μm) and phasmid position (varying from three annuli anterior or three annuli posterior to anus vsat 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. urmiaensisn. sp. and R. striaticeps., The authors acknowledge the University of Zanjan (Iran) for financial support, Dr Majid Pedram from Tarbiat Modares University for his comments, and grant AGR-136 from ‘Consejería de Economía, Innvovación y Ciencia’ from Junta de Andalucía, and Union Europea, Fondo Europeo de Desarrollo regional, ‘Una manera de hacer Europa’.

Stunt nematodes are characterized by phenotypic plasticity, with overlapping morphology and morphometry leading to potential misidentification. Consequently, the application of integrative taxonomic approaches is useful to species delimitation based on a combination of different perspectives, e.g. morphology and DNA sequences. We conducted nematode surveys in cultivated and natural environments in Spain and the USA, from which we identified 18 known species of the family Telotylenchidae and two new taxa within the studied samples. These species were morphologically, morphometrically, and molecularly characterized. The results of light and scanning electron microscopic observations, and molecular and phylogenetic analysis also allowed two new species to be distinguished, described herein as Bitylenchus hispaniensis sp. nov. and Tylenchorhynchus mediterraneus sp. nov. The phylogenetic analysis was carried out using molecular data from nuclear ribosomal DNA genes [D2–D3 expansion segments of the large ribosomal subunit (28S), internal transcribed spacer (ITS), and partial small ribosomal subunit (18S)]. We also provide here a test of alternative hypotheses that confirms the monophyly of both Tylenchorhynchus and Bitylenchus sensu Siddiqi's classification but does not support Fortuner & Luc's conceptual view of Tylenchorhynchus as a large genus. Ancestral state reconstructions of several diagnostic morphological characters using a maximum parsimony approach showed congruence in morphological and molecular evolution for stylet knob inclination and tail tip annulation. Our analysis emphasizes some of the problems related to the taxonomy and phylogeny of nematodes of Telotylenchinae. © 2014 The Linnean Society of London

After introducing its history, the most relevant morphological features of Oriverutus are explained, illustrated (light and scanning electron microscope pictures) and discussed. The taxonomy of the genus is analysed based on the study of all the nominal species, and an emended diagnosis is provided. Its relationships with the closest genera are discussed, and some reflections are made on its phylogeny. Ecanema and Mammillonema are confirmed as junior synonyms of Oriverutus, Inbionema is regarded as its junior synonym also, whereas Paroriverutus is considered to deserve separate generic status. Consequently, several nomenclatorial changes are derived: Paroriverutus ivorensis is retained under Paroriverutus, Drepanodorylaimus macramphidius and Oriverutus longicaudatus are transferred to Paroriverutus, and Inbionema biforme to Oriverutus. An updated list of Oriverutus species is provided as well as a key to the identification of its didelphic species and a compendium of their morphometrics.

The nematode Rotylenchus paravitis n. sp. infesting roots of commercial sunflowers in southern Spain is described. The new species is characterised by a truncate lip region with 7–9 annuli and continuous with the body contour, lateral fields areolated at pharyngeal region only, body without longitudinal striations, stylet length of 44–50 μm, vulva position at 43–54%, tail rounded to hemispherical with 12–18 annuli. A comparative phenetic study based on a multivariate principal component analysis was developed to determine potential species discrimination. The degree of variation for most characters among specimens of Rotylenchus paravitis n. sp. and R. vitis was comparable to that observed among specimens belonging to each of the two studied populations of R. robustus from Spain and USA. Molecular comparison of the partial 18S, D2-D3 expansion segments of 28S-rRNA, ITS1-rRNA, partial COI and hsp90 from R. paravitis n. sp. and R. vitis , and other species in the genus, clearly supports the proposal of R. paravitis n. sp. as a new species. Consequently, R. paravitis n. sp. should be considered as an example of cryptic speciation within the genus Rotylenchus . PCR-ITS-RFLP was provided for diagnostics of R. paravitis n. sp. and PCR with specific primers were also developed for diagnostics of this new species, R. vitis and R. robustus . The results of the phylogenetic analysis based on the sequences of the D2-D3 expansion regions of the 28S, ITS1-rRNA genes, and the partial COI , have proven to be a powerful tool for providing accurate species identification and assessing phylogenetic relationships within the genus Rotylenchus . Phylogenetic testing of D2-D3 expansion segments of 28S-rRNA gene sequences did not refute the monophyly of the genera Rotylenchus , Helicotylenchus , Hoplolaimus , based on tree topologies and the Shimodaira–Hasegawa test even with the split in several clades for some of the genera.

Root-lesion nematodes of the genus Pratylenchus are among the most damaging nematodes for crop and ornamental plants worldwide. There are about 75 described species in this genus with a wide host range, but a difficult diagnosis because of morphological similarities and overlapping of morphometric characters among species. Four species of Pratylenchus were detected parasitizing cultivated and ornamental plants in Costa Rica: Pratylenchus bolivianus, P. gutierrezi, P. pseudocoffeae, and P. zeae; while P. panamaensis was detected in coffee in the type locality at Panama. The specimens were identified using morphological and molecular methods. Morphometrics and morphology using light and scanning electron microscopy are given for all of them. The presence of P. bolivianus and P. pseudocoffeae are reported for the first time in Costa Rica. The molecular and morphological variability associated with former populations of P. gutierrezi showed that we are in front of complex of species. This has been resolved with the study of topotype populations of P. gutierrezi and P. panamaensis combined with rDNA sequences (D2-D3 expansion segments of 28S and ITS). Our results, including SEM en face view data on topotypes of P. gutierrezi and P. panamaensis demonstrated that both species are almost undistinguishable morphologically, but clearly separated molecularly with D2-D3 expansion segments of 28S (89 % similar, 84 nucleotides and 19 indels) and ITS rDNA (only 36 % coverage with a 88 % similarity value). Consequently, P. gutierrezi and P. panamaensis need to be maintained as different valid taxa. Molecular data on D2-D3 expansion segments of 28S and ITS rDNA of topotypes of P. panamaensis were also coincident (99 % similarity) with root-lesion nematodes parasitizing coffee in Guatemala and Costa Rica, and banana in Madeira, and previously identified as P. gutierrezi (K1-AF170440, K2-AF170441, FR692277, respectively), which need to be considered conspecific with P. panamaensis. These results showed us the necessity of integrative taxonomy in the identification and characterization of Pratylenchus spp., This research was supported by grant AGR-136 from ‘Consejería de Economía, Innvovación y Ciencia’ from Junta de Andalucía, and Unión Europea, Fondo Europeo de Desarrollo regional, “Una manera de hacer Europa”. The fifth author is a recipient of a “Juan de La Cierva” contract from Ministerio de Economía y Competitividad of Spain.

A new and a known species of Rotylenchus from Crete, each collected from the rhizosphere of olive, are described and illustrated based on morphological, morphometric and molecular studies. Rotylenchus cretensis n. sp. is characterised by having a truncate lip region with irregular longitudinal striation, lateral field areolated only in pharynx region, stylet length less than 41 μm, vulva located at 53–59 %, conoid-rounded to dorsally convex-conoid female tail with 7–11 annuli and specific D2-D3 of 28S, ITS, and partial 18S rRNA. Rotylenchus cretensis n. sp. appears to be similar to R. urmiaensis, having overlapping character ranges. Rotylenchus cretensis is also similar to R. striaticeps from which has got shorter stylet length (35.5–41.5 vs 39–50 μm), female tail shape (conoid-rounded to dorsally convex-conoid vs rounded), shorter spicules length (34–40 vs 41–50 μm), and phasmid position (varying from at level to three annuli posterior to the anus vs at level to seven annuli anterior to anus). Multivariate analysis of variance performed on R. cretensis n. sp., as well as two populations of R. striaticeps and R. urmiaensis from Iran on combined morphometric characters data set revealed a significant effect by species populations, indicating that closely morphological and morphometrically species differed significantly from each other. Additionally, analysis of variance showed that morphometric characters such as lip region width, distance from phasmid to tail tip (PHS) or a ratio can be used as key morphometric characters for species differentiation in this group. The results of phylogenetic analyses based on D2-D3 region, ITS of rRNA, and the partial 18S sequences confirmed the close molecular relationships between R. cretensis n. sp., R. urmiaensis and R. striaticeps, but clearly support the proposal of R. cretensis n. sp. as a new species. Also, the recognition of this cryptic species within Rotylenchus shows that the biodiversity of these nematodes is still not fully understood and requires further studies. Additionally, R. cypriensis is described and molecularly analysed for first time in Greece., The present research was partially funded by grant KBBE 219262 ArimNET-ERANET FP7 2012–2015 Project PESTOLIVE ‘Contribution of olive history for the management of soilborne parasites in the Mediterranean basin’ from Hellenic Agricultural Organization-DEMETER and Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), grant AGR-136 from ‘Consejería de Economía, Innvovación y Ciencia’ from Junta de Andalucía, and Union Europea, Fondo Europeo de Desarrollo regional, ‘Una manera de hacer Europa’. I. G. Birmpilis was employed by the ARIMNET-PESTOLIVE project.

Morphologial, biochemical, molecular and karyological analyses of different populations and races of the stem and bulb nematode Ditylenchus dipsaci have suggested that it represents a species complex, of which only D. dipsaci sensu stricto and its morphologically larger variant, known as the giant race of the stem and bulb nematode, are plant parasites of economic importance. The present study singles out the giant race from this complex, herein described as a new species named Ditylenchus gigas n. sp., on the basis of morphological and molecular data obtained from several populations collected from broad beans in southern Italy, southern Spain and Lebanon. The new species epithet, which refers to the large body size of the nematode with respect to the normal races, must be considered to be conspecific with the D. dipsaci ‘giant race’ from Fabaceae in recent literature. Morphologically, the new species is characterized by a body size 1AE5‐2 times longer than the ‘normal race’, stylet delicate (11AE5‐13AE0 lm long) with knobs distinctly sloping backwards, and long post-vulval uterine sac (81‐150 lm long). Results of molecular analysis of rDNA sequences including the ITS1-5.8S-ITS2 region, the D2‐D3 fragment of the 28S gene, the small 18S subunit, the partial mitochondrial gene for cytochrome c oxidase I (mtCOI), and hsp90 gene sequences, support the new taxonomic species status for the former D. dipsaci giant race from Vicia faba, and clearly distinguish D. gigas n. sp. from D. dipsaci sensu stricto.

Three Costa Rican species with a simple uterus, two new and one known, belonging to the genus Oriverutus are described. Descriptions, measurements and illustrations are provided. A detailed study of O. asaccatus, including SEM pictures, is presented and its diagnosis emended; O. sturhani is regarded as its junior synonym. Oriverutus costaricensis sp. n. is distinguished by its body 1.07-1.24 mm long, lip region offset by constriction and 14-15 μm broad, odontostyle 23.5-24 μm long, neck 277-353 μm long, pharyngeal-expansion 125-179 μm long or 45-51% of total neck length, cardia asymmetrical, a dorsal cell mass present at level of pharyngo-intestinal junction, female genital system amphidelphic, V = 45-48, tail conical and slightly bent dorsad at the end (42-43 μm long, c = 25-29, c′ = 1.7-1.8), and males unknown. Oriverutus hemihystera sp. n. is characterised by its body 0.92-1.17 mm long, lip region offset by shallow depression or almost continuous and 10-11.5 μm broad, odontostyle 22-24 μm long, neck 280-330 μm long, pharyngeal expansion 115-138 μm long or 41-43% of total neck length, female genital system amphidelphic but anterior genital branch reduced, V = 43-45, tail conical and slightly bent dorsad at the end (62-65 μm long, c = 15-18, c′ = 3.1-3.4), and males unknown.

High infection rates of European holly (Ilex aquifolium) feeder roots by an unknown root-knot nematode were found in a holly forest at Arévalo de la Sierra (Soria province) in northern Spain. Holly trees infected by the root-knot nematode showed some decline and low growth. Infected feeder roots were distorted and showed numerous root galls of large (8–10 mm) to moderate (2–3 mm) size. Morphometry, esterase and malate dehydrogenase electrophoretic phenotypes and phylogenetic trees of sequences within the ribosomal DNA (rDNA) demonstrated that this nematode species differs clearly from other previously described root-knot nematodes. Studies of host-parasite relationships showed a typical susceptible reaction in naturally infected European holly plants, but did not reproduce on a number of cultivated plants, including tomato, grapevine, princess-tree and olive. The species is described here, illustrated and named as Meloidogyne silvestris n. sp. The new root-knot nematode can be morphologically distinguished from other Meloidogyne spp. by: (i) roundish perineal pattern, dorsal arch low, with fine, sinuous cuticle striae, lateral fields faintly visible; (ii) female excretory pore level with stylet knobs, or just anterior to them, EP/ST ratio about 0·8; (iii) second-stage juveniles with hemizonid located 1 to 2 annuli anterior to excretory pore and short, sub-digitate tail; and (iv) males with lateral fields composed of four incisures, with areolated outer bands. Phylogenetic trees derived from maximum parsimony analysis based on 18S, ITS1-5·8S-ITS2 and D2–D3 of 28S rDNA showed that M. silvestris n. sp. can be differentiated from all described root-knot nematode species, and it is clearly separated from other species with resemblance in morphology, such as M. ardenensis, M. dunensis and M. lusitanica.

There is growing interest in the application of soil enzymes and nematode community indices as indicators of changes in soil quality under contrasting management practices. Although an abundant literature on this subject has arisen during the last 10 years, most of the studies have focused on measuring many soil quality indicators at a single or a few sampling times. However, soil enzyme activities show a natural temporal variability which could mask the variability due to the type and timing of soil management practices. In this study, we compared soil enzymes, nematode communities and physical–chemical soil properties in three pairs of organic and neighbouring conventional olive orchards. Dehydrogenase, β-glucosidase, arylsulfatase, acid and alkaline phosphatases activities, and potential nitrification were studied during an annual cycle, and variability due to sites, replicates within a site, management practices and seasonality has been accounted for. In addition, several nematode community indicators were also studied on one occasion. The geometric mean of enzymes activities (GMea), used as an integrating soil quality index, was validated through an independently performed principal component analysis (PCA). Seasonal variability of individual soil enzymes ranged from 29 to 71%, without a consistent temporal trend. Management system explained, on average, a maximum of 26.3 and 15% of the variability found for soil enzymes and nematode community indicators, respectively. Most of the variability found in both sets of indicators was due to different localities (up to 58 and 45% for soil enzyme and nematode community indicators, respectively) and replicates within a plot (up to 51 and 86%, respectively). Organic management resulted in significantly higher soil enzyme activities. However, differences were dependent on site and sampling. For nematode community indicators, the organic farms showed higher values only for one site. These results reveal the need for extensive comparative assessments to draw clear conclusions on the improvement of soil quality under sustainable management practices. The GMea was significantly higher in organic than in conventional managed plots, independently of the sampling and, moreover, showed significant correlation with the first axis of the PCA. In addition, the GMea, and scores on the first axis were highly correlated with some of the nematode indices. Therefore, the GMea was a suitable tool to condense the whole set of soil enzyme values in a single informative numerical value, which was more sensitive to management practices than nematode community indicators.

New observations on three similar species of the genus Enchodelus, namely E. groenlandicus, E. macrodorus and E. saxifragae, are provided on the basis of material collected in the southern Iberian Peninsula. Enchodelus groenlandicus is redescribed, this being the first record of the species after its original description 80 years ago. An emended diagnosis is given for E. macrodorus in addition to a compendium and analysis of its previous records. Enchodelus saxifragae, certainly the most widely distributed species in the studied area, is also redescribed. Measurements, illustrations, including LM and SEM, and remarks on the identity of the three species, are presented. Together with E. distinctus and E. microdoroides, the three species form a species group characterised by a long odontostyle (>35 μm), flanged odontophore, tripartite uterus and short, rounded tail. These five species are compared in detail and a key to their identification provided.

Abstract Two new and one known species belonging to the genus Enchodelus from the southeast of the Iberian Peninsula are described and illustrated. Enchodelus ameliae sp. n. is a medium-sized nematode (1.37-1.55 mm) with lip region offset by constriction, odontostyle 30-32 μm long, female reproductive system amphidelphic with tripartite uterus, vulva almost equatorial (V = 47-50), spicules 49-60 μm long, 11-14 spaced ventromedian supplements and short rounded conoid tail. Enchodelus longispiculus sp. n. is characterised by its medium-sized body (1.32-1.87 mm), lip region offset by shallow depression, odontostyle 27-31 μm long, female reproductive system amphidelphic with tripartite uterus, vulva pre-equatorial (V = 41-48), spicules 63-72 μm long, 8-14 spaced ventromedian supplements and short rounded conoid tail. Enchodelus hopedoroides is redescribed on the basis of Andalusian material and observations on the Swiss holotype. These three species share some features, such as medium-sized odontostyle (ca 30 μm long), tripartite uterus and short, rounded, tail. They are compared in detail with other similar species, namely E. altherri, E. analatus, E. arcticus, E. georgiensis, E. hopedorus and E. ponorensis. A key to their identification is provided.

Two new and two known species belonging to the genus Enchodelus from the southeast of the Iberian Peninsula are described and illustrated. Enchodelus porosus sp. n. is characterised by its medium-sized body (1.39-1.70 mm), lateral chord bearing conspicuous pores surrounded by a refractive ring, odontostyle 16.5-18.0 μ m long, female reproductive system amphidelphic with uterus bipartite including irregular refractive bodies, pars refringens vaginae absent, spicules 39-45 μ m long, 4-6 separated ventromedian supplements and ventrally curved conical tail. Enchodelus veletensis sp. n. is a medium-to large-sized nematode (1.78-2.06 mm), with odontostyle 29-31 μ m long, female genital system amphidelphic with uterus bipartite, vagina bearing two sclerotisations surrounded by a spherical pars distalis and ventrally curved conical tail. In addition, E. morgensis is redescribed and new observations on E. brevidentatus are provided and discussed.

Morphological and molecular analyses of a stem nematode causing a severe disease on infected sowthistle (Sonchus bulbosus) plants, involving the formation of gall-like structures on infected leaves and stems, have led to the description of a new species named Ditylenchus oncogenus n. sp. Morphologically, the new species is characterized by a medium to large body size (all adults more than 1 mm in length); a delicate stylet (9.0–11.0 μm long) with minute, rounded knobs; a long post-vulval uterine sac (c. 65% of the vulva–anus distance); six incisures at the lateral fields and characteristic D. destructor-pattern of spicules (with pronounced ventral tumulus and anteriorly pointed, less sclerotized, cuticle parts present within the lamina). The results of molecular analysis of rRNA gene sequences, including the D2–D3 expansion regions of 28S rRNA, internal transcribed spacer (ITS) rRNA, partial 18S rRNA gene, the protein-coding mitochondrial gene, cytochrome oxidase c subunit I (COI), and the heat-shock protein 90 (hsp90) gene, support the new species status. The results of a host-suitability test indicated that the new species does not parasitize potato (Solanum tuberosum) tubers and broad bean (Vicia faba) seedlings. Histopathological observations on naturally infected sowthistle tissues revealed that D. oncogenus n. sp. causes floral stem neoplasia and midrib leaf gall formation on the type, and to date only known, host. The galls were characterized by extensive hyperplasia, where several necrotic cells in the neoplasic area were directly damaged by feeding of the nematode, whereas a number of adjacent cells showed typical cytological changes, such as granulated cytoplasm with hypertrophied nuclei and nucleoli., The present work was supported with funds provided by the Italian Ministry of Economy and Finance to the National Research Council for the project ‘Innovazione e Sviluppo del Mezzogiorno' – Conoscenze Integrate per Sostenibilità ed Innovazione del Made in Italy Agroalimentare – Legge n. 191/2009, and partially by grant AGR-136 from ‘Consejería de Economía, Innvovación y Ciencia’ from Junta de Andalucía and and Union Europea, Fondo Europeo de Desarrollo regional, ‘Una manera de hacer Europa’.

Systematic nematode surveys for criconematids in the coastal sand dunes of southern Spain and on the Atlantic coast of Florida, USA, revealed the presence of three populations of sheathoid nematodes identified as Hemicriconemoides promissus, H. ortonwilliamsi and H. wessoni. All of them belong to the fourth group proposed by Decraemer and Geraert (1992) as they are characterised by wide body annuli ca ≥ 5 μm wide and a stylet ca 50 μm long, although all have a distinctly different female tail shape. Comparative SEM studies on H. cocophillus, H. mangiferae, H. brachyurus and H. promissus were done. SEM studies from paratype material and female specimens of a newly discovered population from Spain, confirmed the absence of lateral vulval flaps for both H. promissus populations, justifying the rejection of the synonymy proposed by Germani and Anderson (1991), and the re-establishment of H. promissus as a species distinct from H. brachyurus. The present records of H. promissus and H. ortonwilliamsi extend their geographical distribution from Italy to an additional Mediterranean country and constitute the first reports of both species in Spain. Additional morphometric data and illustrations of a Pensacola, FL, USA, population of H. wessoni, the type species of the genus, are also presented.

6 pages, 2 figures.-- Full-text version available at: http://www.ias.csic.es/pcastillo/nematology-6-749-754.pdf, SEM studies on a Meloidogyne baetica population provided additional details of the external morphology for female, male and second-stage juveniles. The labial disc in female and male specimens is fused with the medial lips forming a single structure. In second-stage juveniles the lateral lips are triangular with rounded margins. The amphidial opening for all life stages appears oval to rectangular in shape and is located between the labial disc and lateral lips. Lateral fields of male and second-stage juveniles have four incisures irregularly areolated along the entire body. The results of a host-range study for additional natural hosts of M. baetica conducted in wild olive communities growing at Vejer de la Frontera (Cádiz province) in southern Spain are also reported. Apart from the type host, M. baetica was found to infect two natural woody host plants, lentisc (Pistacia lentiscus) and Aristolochia baetica. Hostparasite relationships in these new hosts confirmed the typical susceptible reaction observed in wild and cultivated olives. Similarly, the reproductive fitness, evaluated as the number of eggs per egg mass, was not significantly different in all plant hosts. No infections or galled roots were observed in herbaceous plant species studied and M. baetica must therefore be considered as a parasite of woody plants.

Abundant material of the nematode species Chitwoodiellus parafuscus (Peña-Santiago, 1991) Jiménez-Guirado & PeñaSantiago, 1992 collected from 17 localities in the south east of the Iberian Peninsula has been studied. Wide intraspecific variability in its measurements and ratios has been noted and analysed. Some of its morphological features are re-examined and revised, and a new concept of the species is proposed. SEM illustrations of this species, and also of the genus, are provided for the first time. Finally, a new diagnosis of the genus Chitwoodiellus and a compendium of its species are given.

Two new species of the genus Discolaimus Cobb, 1913 are described from southeastern Spain. D. mariae sp. n. is distinguished by its large size (L = 2.4-3.3 mm), lip region diameter 29-35 μm, odontostyle 23-25 μm, pharyngeal expansion occupying two-thirds of the total neck length, presence of dorsal cell bodies close to cardia, V = 46-53, female genital system didelphicamphidelphic, tail conical with rounded terminus (33-39 μm, c = 72-88, c′ = 0.9-1.0) and with a terminal gap in the inner cuticle, and males absent. D. labiatus sp. n. is characterised by being medium sized (L = 0.99-1.20 mm), lip region diameter 14-17 μm wide, labial disc with no radial but six longitudinal grooves, inner (perioral) labial portion forming well developed liplets, odontostyle 10.0-12.5 μm, vulva relatively anterior (V = 39-43), female tail conical with rounded terminus (26-27 μm, c = 37-46, c′ = 1.5-1.7), and male unknown. Scanning electron microscope observations of the species are also presented.

A new mono-sexual root-lesion nematode species, Pratylenchus oleae n. sp., parasitizing roots of olive plants cv. Koroneiki in commercial fields at Ouled Chamekh (central Tunisia), and wild and cultivated olive (cv. Picual) plants in Agua Amarga (southern Spain) is described. The new species is characterised by the female having a lip region slightly offset and bearing three annuli, stylet 16.5 (14.5-17.0) μm long, with prominent rounded knobs, pharyngeal overlapping rather long (22-36) μm, lateral fields areolated and with four incisures and diagonal lines in middle band, spermatheca rounded but non-functional, tail short, conoid-rounded to subcylindrical, usually annulated terminus, males unknown, and a specific D2-D3, ITS1, 18S-rRNA, hsp90 and COI sequences. Morphologically this species is related to P. cruciferus, P. delattrei, and P. kumamotoensis. The results of the phylogenetic analysis based on sequences of the D2-D3 expansion regions of 28S, partial 18S and ITS rRNA genes confirmed the close relationship of P. oleae n. sp. with P. dunensis, P. penetrans, P. pinguicaudatus, from which was clearly separated. A PCR-based diagnostic assay was also developed for identification of P. oleae n. sp. using the species-specific primers Poleae_fw1_4 and Poleae_rv1 that amplify a 547-bp fragment in the internal transcribed spacer (ITS1) region of ribosomal DNA, which clearly separate from other root-lesion nematodes damaging olive such as P. penetrans and P. vulnus. © 2014 Koninklijke Nederlandse Planteziektenkundige Vereniging., This research was supported by a grant 219262 ArimNET_ERANET FP7 2012–2015 Project PESTOLIVE ‘Contribution of olive history for the management of soilborne parasites in the Mediterranean basin’ from Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), grant AGR-136 from ‘Consejería de Economía, Innvovación y Ciencia’ from Junta de Andalucía, and Union Europea, Fondo Europeo de Desarrollo regional, “Una manera de hacer Europa”. The first author is a recipient of a “Juan de La Cierva” contract from Ministerio de Economía y Competitividad of Spain

Rotylenchus arasbaranensis n. sp., a new monosexual species is described and illustrated based on morphological, morphometric and molecular studies. The new species is characterised by having an offset and hemispherical lip region with 5-6 annuli, 32-36 μm long stylet, vulva located at 43.9-59.2% with a single epiptygma and rounded tail, rarely bilobed, with 6-8 annuli. The species R. striaticeps and the male of R. buxophilus are reported for the first time from Iran and R. fragaricus is reported and studied for the second time after its original description. The results of the phylogenetic analyses based on the sequences of the D2- D3 expansion region of the 28S, ITS1-rRNA and the partial 18S rRNA genes were provided for the studied species, confirming their differences from each other and determining the position of them and their relationships with closely related taxa. Also, the validity of Plesiorotylenchus is discussed on the basis of molecular data and its synonymisation (with only one sequence) with Rotylenchus is accepted., The first four authors acknowledge the Iranian National Science Foundation (INSF) and Tarbiat Modares University (Iran) for the financial support; while the sixth to eighth authors acknowledge the financial support by grant AGR-136 from ‘Consejería de Economía, Innvovación y Ciencia’ from Junta de Andalucía, and Union Europea, Fondo Europeo de Desarrollo regional, ‘Una manera de hacer Europa’. SEM pictures were obtained with the assistance of technical staff and the equipment of ‘Centro de Instrumentación Científico-Técnica (CICT)’, University of Jaén.

Two new species of the genus Carcharodiscus are described from southeastern Spain. Carcharodiscus procerus sp. n. is characterised by: a very slender (a = 52 - 62) body 1.67 - 2.17 mm long, lip region offset by constriction and 17 - 18 μm diam., anterior portion of the cheilostome 12 - 13× 7.0- 7.5 μm with abundant denticles on its walls, odontostyle 10 - 12 μm long or ca 66% of the lip region diam., presence of a dorsal cell chord behind the cardia, female genital system amphidelphic, vulva longitudinal and somewhat posterior (V = 52 - 58), presence of cuticular irregularities near the vulva area, tail rounded conoid (22 - 28 μm; c = 70 - 83; c′ = 1.0 - 1.2), and male unknown. Carcharodiscus olearum sp. n. is distinguished by its very slender (a = 51 - 55) and long (L = 2.36 2.79 mm) body, lip region offset by deep constriction and 22 - 27 μm in diam., anterior portion of the cheilostome 16.5- 18.0 × 8.0- 9.5 μm with abundant denticles on its walls, odontostyle 16.0- 17.5 μm long or 0.7 to 0.8 times the lip region in diam., presence of a dorsal cell chord behind the cardia, female genital system amphidelphic, vulva longitudinal and somewhat posterior (V = 50 - 58), tail rounded conoid (25 - 28 μm; c = 89 - 99; c′ = 0.8- 0.9), and male unknown. Carcharolaimus eximius is transferred to Carcharodiscus. A list of the species of the genus and key to their identification are also provided.

Paralongidorus plesioepimikis n. sp. is described and illustrated by light microscopy, scanning electron microscopy and molecular studies from specimens collected in a sandy soil in the rhizosphere of stone pine (Pinus pinea) in Bonares (Huelva Province), southern Spain. The new species is characterised by a very long body (9.71-14.11 mm), an expanded and rounded lip region, with a clear constriction followed by a depression posterior to the amphidial aperture, a very long and flexible odontostyle (202-227 ¿m), guiding ring located at 36.5-44.0 ¿m from anterior end, dorsal pharyngeal gland nucleus in anterior part of bulb, one subventral pair of nuclei near middle of bulb, vulva at 33-38%, and a dorsally convex tail with rounded terminus (32-39 ¿m long). SEM observations showed a very large amphidial fovea with conspicuous aperture ca three-fourths as wide as lip region and cephalic papillae appearing as small apertures, each located just anterior to a distinct cephalic lobe. The sequences of the D2-D3 expansion segments of 28S rRNA, partial 18S rRNA and ITS rRNA gene for P. plesioepimikis n. sp. were obtained. Phylogenetic analyses of P. plesioepimikis n. sp. rRNA gene sequences and of Paralongidorus spp. and Longidorus spp. sequences published in GenBank were done using Maximum Likelihood and Bayesian inference. Paralongidorus species (including P. plesioepimikis n. sp.) clustered together, except for P. bikanerensis which clustered within Longidorus spp. and was clearly separated from all other Paralongidorus spp. in trees generated from the D2-D3 expansion segments of 28S and partial 18S data set. ML analysis using SH-test for the validity of Paralongidorus was performed and showed the validity of the genus using the D2-D3 expansion segment of 28S and partial 18S., This research was supported by grant AGL2009-06955 from ‘Ministerio de Ciencia e Innovación’ of Spain, grant AGR-136 from ‘Consejería de Economía, Innvovación y Ciencia’ from Junta de Andalucía, and the European Social Fund.

Paralongidorus iranicus n. sp., a new bisexual species of the genus, is described and illustrated by light microscopy, scanning electron microscopy and molecular studies from specimens collected in the rhizosphere of Scots pine (Pinus sylvestris) from the Caspian (Khazar) seashore, Nour, northern Iran. Paralongidorus iranicus n. sp. is characterised by the large body size (7.8-11.4 mm), a rounded lip region, clearly set off by a collar-like constriction at level of, or slightly posterior to, the amphidial aperture, and bearing a very large, stirrup-shaped, amphidial fovea, with conspicuous slit-like aperture, a very long and flexible odontostyle ca 170 μm long, guiding ring located at 34 μm from anterior end and males with spicules ca 80 μm long. In addition, data from an Iranian population of P. bikanerensis recovered from the rhizosphere of palm (Phoenix dactylifera L.) in Bam, Kerman province, south-eastern Iran, agree very well and are very close to the original description of the species from India. The D2 and D3 expansion regions of 28S rRNA gene, ITS1, and 18S rRNA sequences were obtained for P. iranicus n. sp. and P. bikanerensis. Phylogenetic analyses of P. iranicus n. sp. and P. bikanerensis rRNA gene sequences and of Longidorus spp. sequences published in GenBank were done using Maximum Likelihood and Bayesian inference. Paralongidorus species (including P. iranicus n. sp.) clustered together; however, P. bikanerensis clustered within Longidorus spp. and was clearly separated from all other Paralongidorus spp. in trees generated from the D2-D3 expansion segments of 28S and partial 18S data set, respectively. © 2012 Koninklijke Brill NV, Leiden., The project was financially supported by the Iranian National Science Foundation (INSF) and Tarbiat Modares University (Iran).

Rotylenchus vitis n. sp., a new amphimictic species infesting soil and roots of commercial vineyards in southern Spain, is described. Rotylenchus vitis n. sp. is characterised by a truncate lip region with 7-9 annuli and continuous with the body contour, lateral fields areolated at pharyngeal region only, body without longitudinal striations, stylet length of 36-48 οm, vulva position at 47-57%, tail rounded to hemispherical with 13-21 annuli. Morphologically, this species is related to R. cazorlaensis, R. capitatus, R. elegans, R. fabalus, R. iranicus, R. labiodiscus, R. montanus and R. troncapitatus. The results of the phylogenetic analysis based on the sequences of the D2-D3 expansion regions of the 28S and ITS1-rRNA genes confirmed the species differentiation and the close molecular relationship between R. eximius and R. montanus, respectively. © 2012 Koninklijke Brill NV, Leiden, The Netherlands., This research was supported by grant AGL2009-06955 from ‘Ministerio de Ciencia e Innovación’ of Spain and the European Social Fund.

A new amphimictic species, Pratylenchus hispaniensis n. sp., parasitising the roots of gum cistus in Andújar (Jaén), southern Spain, is described. The new species is characterised by the presence of numerous males and by the female having a lip region with three annuli, a divided face, a robust stylet (14.5-17.0 μm) with rounded knobs, lateral fields with four lines, V = 80-84, a round spermatheca full of sperm, well developed post-vulval uterine sac and an obliquely truncate tail with irregularly annulated terminus. Morphologically this species is related to P. bhatti, P. kralli, P. mediterraneus, P. pseudofallax and P. thornei. A phenetic study of the 25 most useful diagnostic morphological and allometric characters for Pratylenchus species was done using multivariate factor and linear discriminant analyses. In the factor analysis the first seven factors accounted for 71.1% of the total variance of the characters selected. These factors were related to female tail, pharyngeal overlap, reproductive behaviour, stylet length, L/post-vulval uterine sac ratio, body length and number of lip annuli. Discriminant analysis differentiated Pratylenchus spp. from the three valid species of Zygotylenchus. The results of the phylogenetic analysis based on sequences of the D2-D3 expansion regions of 28S, partial 18S and ITS rRNA genes confirmed the close relationship of P. hispaniensis n. sp. with P. mediterraneus and inferred molecular affinity with P. brzeskii, P. neglectus and P. thornei, in spite of variation in the position of P. hispaniensis n. sp. in the clades. Additional phylogenetic analyses based on the same sets of sequences for P. hispaniensis n. sp., Zygotylenchus guevarai and other Pratylenchidae indicated that Pratylenchus includes several paraphyletic lineages; however, likelihood tests did not reject monophyly of the genus. The inclusion of Pratylenchus, Zygotylenchus, Hirschmanniella, Nacobbus and Apratylenchus in Pratylenchidae was supported.

The occurrence of a male-less population of Sphaeronema alni parasitising chestnut (Castanea sativa) roots and inducing a stelar syncytium is reported for the first time in Pola de Somiedo (Oviedo province), Spain. Morphometric and molecular characters of the Spanish population matched those of a topotype population from Russia. SEM observations showed swollen females having the first lip annulus wider than the second and appearing as a cap-like, circumoral elevation. The second-stage juveniles, having a single band in the lateral fields, were characterised by a non-annulated dome-shaped lip region derived from the fusion of the oral disc with all the lip sectors and lip annuli, and showing slit-like amphidial apertures and an oval prestoma. The sequences of the D2-D3 expansion segments of 28S rRNA, partial 18S rRNA and ITS rRNA gene for the Spanish and topotype populations of S. alni were congruent and matched those deposited in GenBank for another population from Germany, thereby confirming their conspecificity. A PCR-RFLP profile of D2-D3 of 28S rRNA for identification of this species was also provided. The phylogenetic relationships between S. alni populations and representatives of the suborder Criconematina, as inferred from analysis of partial 18S rRNA and D2-D3 of 28S gene sequences obtained in this and previous studies, indicated that S. alni formed a basal clade on the majority consensus Bayesian phylogenetic trees, standing together with Meloidoderita sp. or alone. These findings provide additional evidence of the need to clarify the position of Sphaeronema within Criconematina and its relationships with representatives of Tylenchulinae.

Nematode surveys in indigenous vegetation in northern Spain revealed the presence of a nematode population of the genus Eutylenchus associated with moist sandy soils in the rhizosphere of common reed (Phragmites sp.) on the banks of the Tera river in Garray (Soria province). Morphological and morphometrical studies on this population fits with Eutylenchus excretorius, representing the first report for Spain and southern Europe and the fifth report in Europe after Germany, Poland, Czech Republic and Russia. SEM studies were carried out for the first time on this species and showed four lips separated by deep grooves. Each lip bears an elongated, flexible, recurved projection (seta) 12 (11-13) μm long, proximal third wide, gradually attenuating, distal end rounded. Molecular characterisation of E. excretorius using several genes is provided. The sequence of D2-D3 expansion segments of 28S rRNA gene of this population was identical to a previously studied sample from Germany. Phylogenetic analysis using D2-D3 of 28S rRNA and partial 18S rRNA gene sequences of tylenchid nematodes revealed that E. excretorius clustered with moderate support with Cephalenchus hexalineatus. The position of E. excretorius on majority consensus Bayesian phylogenetic tree reconstructed using heat shock protein 90 gene sequence was not well resolved.

17 pages, 8 figures., A description of a new species of plant parasitic nematodes of the genus Rotylenchus from the family Hoplolaimidae is given and a recognition of Rotylenchus jaeni comb. n., previously known as subspecies R. magnus jaeni, as separate species is proposed. Rotylenchus montanus sp. n. is characterized by a hemispherical lip region with six rarely seven annuli, stylet 33–37 µm, female tail rounded, regularly annulated tip with 12–18 annuli and phasmid located 2–9 annuli anterior to anus. Rotylenchus montanus sp. n. is close to species of the monosexual group R. arsenjevi, R. corsicus, R. fragaricus, R. helicus, R. indorobustus and R. neorobustus, by a number of specific characteristics resulting from its specific matrix code: A5, B1, C1, D4, E2, F2, G3, H2, I2, J2, K2. Molecular characterization of R. montanus sp. n. and other Rotylenchus species are provided using D2–D3 expansion segments of 28S and the ITS1 of rRNA genes. The D2–D3 of 28S rRNA and the ITS1–rRNA sequences of R. montanus sp. n. differed in one nucleotide and in 16–20 nucleotides from those of an unidentified Rotylenchus species from Russia, respectively. Molecular analysis of populations of R. magnus and R. jaeni comb. n. demonstrated differences in the D2–D3 and the ITS1–rRNA sequences. These genetic differences together with some minor morphological characters support that both subspecies should be considered as two cryptic sibling species and warranted their elevation to species rank. The result of phylogenetic analysis of Hoplolaimidae for 45 sequences of the D2 and D3 expansion regions of 28S rRNA gene using Bayesian inference analysis under the complex model is presented. Phylogenetic tree of Rotylenchus species represents seven moderate to highly supported lineages. Grouping of Rotylenchus species within other hoplolaimids and analysis of phylogenetic relationships within the genus Rotylenchus using the ITS1 of rRNA gene sequences are also discussed., The second author acknowledges support from NSF PEET grant DEB-0731516, and the fifth author acknowledges support from Consejería de Innovación Ciencia y Empresa (CICE) of Junta de Andalucía grant P06-AGR-01360.

A new species of awl nematode, Dolichodorus mediterraneus sp. n., is described from southern Spain. The new species is described and illustrated by light microscopy and scanning electron microscopy studies from specimens collected in a sandy soil around roots of cork oak (Quercus suber L.) from Hato Raton, Aznalcázar (Seville), southern Spain. Dolichodorus mediterraneus sp. n. is characterised by a prominent, rounded, lip region, which is offset from the body and has four to six very fine annuli; lateral fields areolated with three lines, ending posterior to anus level; tail 72-122 μm long, abruptly tapering to an acuminate, often spicate, terminus; tail projection 51-79 μ m long; spicules ventrally arcuate, 33-42 μm long; gubernaculum slightly ventrally curved, 14-22 μm long. Scanning electron microscopy observations showed a similar en face pattern to other Dolichodorus spp. Molecular data from the ribosomal large subunit D2-D3 expansion segment of 28S rDNA from paratypes yielded a single fragment of approximately 800 bp. This is the first record of the genus Dolichodorus in Spain and only the second in Europe. A key to species is provided.

Rotylenchus castilloi n. sp., a new bisexual species is described and illustrated based on morphological, morphometric and molecular data. The new species is characterised by having a hemispherical, continuous lip region with an irregular corncob-like appearance under SEM, very long stylet (62–68 µm), vulva located at 49.7–62.2% of body length from anterior end, with a protruding double epiptygma, a rounded to convex-conoid (rarely bi-lobed) tail with 8–12 annuli and specific sequences of D2-D3 segments of 28S and ITS1-rRNA genes. Differences between the new species and four other species of the genus (R. mesorobustus, R. cazorlaensis, R. magnus and R. jaeni) are discussed. Morphologically, the new species can be separated from these species mostly by its body length, lip region characters, stylet length and location of phasmid. Phylogenetic analyses using 721 bp partial sequences of D2-D3 expansion segments of the 28S and 590 bp ITS1-rRNA genes revealed the new species forming a clade with two isolates of R. eximius and two isolates of R. unisexus, two morphologically unrelated species.