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Morphological and molecular analyses of three populations of Meloidoderita whittoni (Sledge & Christie, 1962) comb. n. (syn. Sphaeronema whittoni; Tumiota whittoni) collected in Florida from sweet gum (Liquidambar styraciflua L.) indicated that this species is a representative of Meloidoderita rather than Sphaeronema, where it was included in the original description, or Tumiota, to where it was subsequently transferred. However, this species can be considered an atypical representative of the genus, because it differs from the other species of this genus in having females retaining the eggs inside a thin-walled uterus, which remains encased inside their body. After egg deposition inside the uterus, the female dies and its body is transformed into a persistent tanned sac with a thick cuticle, devoid of ornamentations, which protects the eggs like a heteroderid cyst. The female secretes from the vulva a gelatinous matrix, which becomes hardened in time and encases its body for protection against predation and parasitism by biological antagonists as has been suggested for other tylenchuloid nematodes. No egg deposition outside the female body was observed. Second-stage juveniles of this species have a semi-endoparasitic, rather than endoparasitic, habit as in other known Meloidoderita species. This is the first report of a sphaeronematid having a cyst stage fitting the definition of a heteroderid cyst. Phylogenetic relationships between some species of Tylenchuloidea and Criconematina are analysed using the partial 18S rRNA, the D2-D3 of 28S rRNA and the ITS rRNA gene sequences.

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.

The foliar nematode species Aphelenchoides ritzemabosi is reported attacking sweet basil in glasshouses in the province of Imperia, northwest Italy. The nematode colonised and reproduced within the leaf, petiole and stem tissues. The epidermis and mesophyll were invaded by the nematode which caused internerval discoloration and necrosis and collapse of the palisade and spongy parenchyma. All nematode developmental stages, including eggs, were observed in the leaf tissues. Morphology and morphometrics of A. ritzemabosi from chlorotic and necrotic leaf tissues are presented. Possible control measures, which are complicated by the short life cycle of the nematode, the broad host range, and the short productive cycle of basil, are also discussed, together with the risk of an erroneous field diagnosis caused by difficulty in differentiating the symptoms of basil downy mildew and basil black spot from those of the foliar nematode.

The results of morphological and molecular analyses of a Florida topotype and other populations of Hemicriconemoides strictathecatus showed that this sheathoid nematode consists of two morphotypes, both with an average stylet length of more than 70 μm, but having different tail termini, bluntly pointed or rounded. These findings confirmed the morphological similarity of H. strictathecatus with H. mangiferae, which was considered a junior synonym of this species as previously proposed by Decraemer & Geraert (1992, 1996). Populations of a sheathoid nematode with a stylet length ranging from 62.5 to 72.0 μm from Taiwan, China, South Africa and Venezuela and identified in previous studies as H. strictathecatus were found to be morphologically and molecularly different from this species and are now considered as representatives of H. litchi. Another sheathoid nematode population from Florida, considered to be H. mangiferae by McSorley et al. (1980), was also found to be morphologically and molecularly congruous with H. litchi. During nematological surveys in Florida, a new sheathoid nematode was detected on date palms imported from California into Florida and is described herein as H. phoenicis sp. n. This new species is related morphologically to the H. strictathecatus morphotype with pointed tail terminus. Both have a stylet longer than 70 μm. The new species is phylogenetically related to H. strictathecatus and H. litchi. It differs morphologically from other Hemicriconemoides species by the cuticular ornamentation of the annuli, which are marked by coarse longitudinal ridges, grooves and thick margins. Morphological and molecular characterisations of H. cocophillus from Mozambique and Florida, USA are also elucidated in this study. New phylogenies of the genus Hemicriconemoides as inferred from the analyses of the ITS rRNA, D2-D3 of 28S rRNA and partial coxI gene sequences are provided., Pablo Castillo and Juan E. Palomares-Rius acknowledge support from grant AGR-136 from ‘Consejería de Economía, Innvovación y Ciencia’ from Junta de Andalucía, and the European Social Fund and Sergei A. Subbotin acknowledges support from the Russian Foundation of Basic Research, project number 14-04-00953.

Morphological identification of spiral nematodes of the genus Helicotylenchus is a difficult task because most characters used for their diagnosis vary within species. In this paper we provide morphological and molecular characterisations of several spiral nematodes, H. broadbalkiensis, H. digonicus, H. dihystera, H. microlobus, H. paxilli and H. pseudorobustus, collected in different geographical areas of USA, Switzerland, Italy, New Zealand, Spain, UK, South Korea and Russia. We suggest that H. microlobus and H. pseudorobustus are valid species separated from each other morphologically and molecularly. Seven species with distinct molecular characteristics are also distinguished, but are not ascribed morphologically to any specific taxon because of the low number of specimens available. Phylogenetic relationships of H. pseudorobustus with other Helicotylenchus species are given as inferred from the analyses of 154 sequences of the D2-D3 of 28S rRNA gene and 37 sequences of ITS rRNA gene., This research was partially supported by grant AGL2012-37521 from ‘Ministerio de Economía y Competitividad’ of Spain, grant P12-AGR 1486 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’, and the Russian Foundation of Basic Research, project number 14-04-00953.

A population of Xiphinema barense from wild olive trees in Torre Pozzella, Brindisi province, southern Italy, is described using both morphological and molecular studies and compared with the description of the type specimens. The wild olive nematode population agrees very well with all morphometrics provided in the original description. However, detailed observations of the lumen of the tubular portion of the uterus in paratypes and specimens of the new population revealed a clear pseudo-Z-organ with small granules mixed with crystalloid bodies which were previously undetected. Photomicrographs of adult paratypes, which were lacking in the original description, and of specimens of the new population from wild olive trees are provided. The results of the phylogenetic analyses based on the sequences of the D2-D3 expansion regions of the 28S rRNA gene and ITS rRNA genes confirm the species differentiation and indicate the phylogenetic position of X. barense and its relationship with closely related species., The present research was partially funded by the grant 219262 ArimNET_ERANET FP7 2012-2015 Project PESTOLIVE “Contribution of olive history for the management of soilborne parasites in the Mediterranean basin”; 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”.

During a survey for Trichodoridae in cultivated and natural environments, mainly from southern Spain, 7 new Trichodorus species were found. Four of them, T andalusicus n. sp., T asturanus n. sp., T silvestris n. sp. and T parasilvestris n. sp., belong to the T lusitanicus morpho-species group characterised in the male by the slightly ventrally curved spicules with a mid-blade constriction with bristles, and in the female by well developed, rounded triangular to quadrangular, vaginal sclerotised pieces. They were mainly differentiated based upon differences in body length, onchiostyle length, spicule shape and number of ventromedian cervical papillae in the male, and size and shape of the vaginal sclerotised pieces in the female. The presence of the T lusitanicus morpho-species group with 8 species, apparently endemic to the Iberian Peninsula, could point to a recent speciation event. Additionally, 3 new species, T onubensis n. sp., T iliplaensis n. sp. and T paragiennensis n. sp., more closely resembling the morpho-species group of T sparsus, to which the Spanish species T giennensis also belongs, were identified. They were differentiated based on body length, length of onchiostyle and position of the secretory-excretory pore and, in the male, by length and shape of the spicules and number of ventromedian cervical papillae and in the female by the vaginal sclerotised pieces. Molecular support to differentiate the new species using the D2-D3 expansion segments of 28S rDNA is also provided. In addition, a new population of T variabilis from Greece was studied as well as T lusitanicus type specimens, and a population of T giennensis and T lusitanicus were also sequenced., This research was supported by grant AGL2009-06955 from 'Ministerio de Ciencia e Innovacion' of Spain, grant AGR-136 from Consejeria de Economia, Innvovacion y Ciencia from Junta de Andalucia, and the European Social Fund. The authors thank J. Martin-Barbarroja and G. Leon-Roper from IAS-CSIC for excellent technical assistance, and M. Montes Borrego (IAS-CSIC) for his help in sampling., info:eu-repo/semantics/publishedVersion

Paralongidorus litoralis sp. n., a new bisexual species of the genus, is described and illustrated by light microscopy, scanning electron microscopy and molecular studies from specimens collected in a coastal sand dune soil around roots of lentisc (Pistacia lentiscus L.) from Zahara de los Atunes (Cadiz), southern Spain. Paralongidorus litoralis sp. n. is characterised by the large body size (7.5-10.0 mm), a rounded lip region, clearly offset from the body by a collar-like constriction, and bearing a very large stirrup-shaped, amphidial fovea, with conspicuous slit-like aperture, a very long and flexible odontostyle ca 190 μm long, guiding ring located at 35 μm from anterior end, and males with spicules ca 70 μm long. In addition, identification data of a Spanish population of P. paramaximus Heyns, 1965 recovered from sandy soil of a commercial citrus orchard at Alcala de Guadaira (Seville), southern Spain, agree very well with the original description of the species from South Africa. The 18S rRNA and D2 and D3 expansion regions of 28S rRNA gene sequences were obtained for P. litoralis sp. n. and P. paramaximus. Phylogenetic analyses of P. litoralis sp. n. and P. paramaximus rRNA gene sequences and of Longidoridae sequences published in GenBank were done using maximum likelihood and Bayesian inference. In trees generated from the 18S data set Paralongidorus clustered as an external clade from Longidorus, and in trees generated from D2-D3 of 28S dataset Paralongidorus was monophyletic and nested within Longidorus. Maximum likelihood test supported the hypothesis of validity of the Paralongidorus genus.

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.

7 pages., In the past, the distribution of Meloidogyne hispanica, the Seville root-knot nematode, appeared to be restricted to the southern part of Spain and Prunus spp.; however, its distribution has been confirmed to be worldwide because it occurs in all continents (Europe, Africa, Asia, Australia, and North, Central, and South America). Differentiation of M. hispanica from other Meloidogyne spp., mainly M. arenaria, can be very difficult using morphological and biological traits data. These species are quite similar and can be regularly confused in inaccurate taxonomic comparisons. In this study, species-specific polymerase chain reaction (PCR) and phylogenetic analysis of sequences from three ribosomal (r)DNA regions (18S, internal transcribed spacer [ITS]1-5.8S-ITS2, and D2-D3 of 28S) were used to characterize three M. hispanica isolates from different geographical origins (Brazil, Portugal, and Spain). Molecular analyses showed identical sequences for all three isolates for the three rDNA regions. Maximum parsimony analysis of the three rDNA regions and the species-specific PCR demonstrated and supported the differentiation of M. hispanica from M. incognita, M. javanica, and M. arenaria and from all described root-knot nematode species.

10 pages, 6 figures.-- PMCID: PMC2586475., Diagnosis of an Argentinean population of Nacobbus sp. infecting sweet pepper (lamuyo) was carried out including morphology, scanning electron microscopy, and molecular studies. In light of our morphometric, molecular and host-range results, we consider the studied population to belong to N. aberrans s. l., and by host range tests the population is assigned to the "sugar beet group." ITS-PCR analysis on individual male and immature female specimens of this population yielded amplification products of approximately 922 bp. RFLP profiles and sequencing of the ITS region revealed that, in addition to the host group, the present population can be assigned to the "Argentina 2" group. Disease development and histopathology were investigated with glasshouse observations using tomato, pepper, sugar beet and potato seedlings exposed to nematode infection for 45 days at 28 ± 2°C. Histopathology of tomato roots confirmed that all immature stages and young females and males are migratory, whereas mature females are obligate sedentary endoparasites. Rather than syncytia, large regions of cortical necrosis and cavities were detected in tomato swellings infected by juveniles. However, syncytia were associated only with adult females. Large root galls, hyperplasia, abnormal proliferation of lateral roots and asymmetry of root structure were common anatomical changes induced by the nematode feeding in tomato roots.

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 ¡Ý 5 ¦Ìm wide and a stylet ca 50 ¦Ìm 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.

Hemicriconemoides macrodorus n. sp. is described and illustrated from a bisexual population collected in a natural habitat at Santa Elena, Jaén, southern Spain. The new species falls into the 'group 2', based on lip patterns (Decraemer & Geraert, 1992), which contains 13 other species characterised by a cephalic region with an offset, raised, narrower oral disc, followed by broader head annuli. The main distinctive characters of the new species are: lip region truncate, very long stylet (90-100 μ m), long body 548-750 μ m, R = 127-148, conical tail, VL/VB = 1.0-1.5, spined juvenile cuticular ornamentation (multispined scales, indented at their edges) arranged in ten alternate rows, and male lateral field with four incisures. Morphometric data, illustrations and brief descriptions are presented for an Italian population of H. ortonwilliamsi Ye & Siddiqi, 1994, while, for the first time, morphometric data and illustrations are given for the male and the juvenile of H. alexis Vovlas, 1980.

High infection rates of European sea rocket feeder roots by an unknown root-knot nematode were found in a coastal dune soil at Cullera (Valencia) in central eastern Spain. Morphometry, esterase and malate dehydrogenase electrophoretic phenotypes and phylogenetic trees 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 sea rocket plants and in artificially inoculated tomato (cv. Roma) and chickpea (cv. UC 27) plants. The species is herein described and illustrated and named as Meloidogyne dunensis n. sp. The new root-knot nematode can be distinguished from other Meloidogyne spp. by: (i) perineal pattern rounded-oval, formed of numerous fine dorsal and ventral cuticle striae and ridges, lateral fields clearly visible; (ii) female excretory pore at the level of stylet knobs, EP/ST ratio 1.6; (iii) second-stage juveniles with hemizonid located 1 to 2 annuli anteriorly to excretory pore and long, narrow, tapering tail; and (iv) males with lateral fields composed of four incisures anteriorly and posteriorly, while six distinct incisures are observed for large part at mid-body. Phylogenetic trees derived from distance and maximum parsimony analyses based on 18S, ITS1-5.8S-ITS2 and D2-D3 of 28S rDNA showed that M. dunensis 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. duytsi, M. maritima, M. mayaguensis and M. minor.