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Summary: Rotylenchus bunae n. sp. was discovered in the coffee rhizosphere in Gera district of Jimma, Ethiopia, and has been morphologically and molecularly characterised. The new species is identified by a female body length of 725-876 μ m, hemispherical lip region with 4-5 lip annuli, stylet length of 28-30 μ m, lateral field areolation only in the pharyngeal region, no cuticular striations, pharyngeal gland overlapping intestine dorsally by 15-26 μ m, double epiptygma, no clear spermathecae, vulva position at 54-58% of body length from anterior end, prominent fasciculi in mid and posterior body, rounded or sometimes slightly truncated, coarsely crenated tail with 11-13 annuli, and phasmids located at 7-16 annuli anterior to anus. No males were detected. This species was found closely related to other African Rotylenchus species, such as R. unisexus and R. wimbii ; however, it could be well separated from them by both morphology and molecular data (D2-D3 of 28S and partial 18S of rDNA). [ABSTRACT FROM AUTHOR]

Root-lesion nematodes of the genus Pratylenchus are an important pest parasitizing a wide range of vascular plants including several economically important crops. However, morphological diagnosis of the more than 100 species is problematic due to the low number of diagnostic features, high morphological plasticity and incomplete taxonomic descriptions. In order to employ barcoding based diagnostics, a link between morphology and species specific sequences has to be established. In this study, we reconstructed a multi-gene phylogeny of the Penetrans group using nuclear ribosomal and mitochondrial gene sequences. A combination of this phylogenetic framework with molecular species delineation analysis, population genetics, morphometric information and sequences from type location material allowed us to establish the species boundaries within the Penetrans group and as such clarify long-standing controversies about the taxonomic status of P. penetrans , P. fallax and P. convallariae . Our study also reveals a remarkable amount of cryptic biodiversity within the genus Pratylenchus confirming that identification on morphology alone can be inconclusive in this taxonomically confusing genus. [ABSTRACT FROM AUTHOR]

Root-knot nematodes, Meloidogyne spp., cause huge economic losses worldwide. Currently, three Meloidogyne spp. are present on the quarantine A2 list of EPPO, M. chitwoodi, M. fallax and M. enterolobii. As a quarantine organism, M. fallax has been detected in England and Northern Ireland on sport turf in 2011, and in England on leek in 2013. However, its presence in Ireland has probably been overlooked since 1965, when Mr. John F. Moore and Dr. Mary T. Franklin had detected a new Meloidogyne species for that time. While the relevant data was recorded and a preliminary manuscript describing the species was prepared but never submitted for publication, and together with the original slides, pictures and drawings, it was restudied recently. We compared the population of Irish Meloidogyne sp. to other similar Meloidogyne spp. Careful observation and comparison shows that it belongs to M. fallax. The characters found to be common for Irish Meloidogyne sp. and M. fallax are female stylet length (14.6 μm) with oval to rounded basal knobs, oval shaped perineal pattern with moderately high dorsal arch, slender stylet in males (18.5 μm) with set off and rounded basal knobs, slightly set off male head with one post-labial annule and incomplete transverse incisures, and second-stage juveniles with large and rounded stylet basal knobs, and a gradually tapering tail (46.9 μm) with a broadly rounded tip and a clearly delimitated smooth hyaline part sometimes marked by constrictions (12.9 μm). The host test and gall formation also correspond to M. fallax. The identification could not be additionally supported by molecular analysis, as we were unable to extract DNA from the old permanent slides. Nevertheless, our study reveals that the Meloidogyne species detected in Ireland in 1965 belongs to M. fallax. [ABSTRACT FROM AUTHOR]

The root-knot nematode Meloidogyne ulmi is synonymised with Meloidogyne mali based on morphological and morphometric similarities, common hosts, as well as biochemical similarities at both protein and DNA levels. M. mali was first described in Japan on Malus prunifolia Borkh.; and M. ulmi in Italy on Ulmus chenmoui W.C. Cheng. Morphological and morphometric studies of their holo- and paratypes revealed important similarities in the major characters as well as some general variability in a few others. Host test also showed that besides the two species being able to parasitize the type hosts of the other, they share some other common hosts. Our study of the esterase and malate dehydrogenase isozyme phenotypes of some M. ulmi populations gave a perfectly comparable result to that already known for M. mali. Finally, phylogenetic studies of their SSU and LSU rDNA sequence data revealed that the two are not distinguishable at DNA level. All these put together, leave strong evidences to support the fact that M. ulmi is not a valid species, but a junior synonym of M. mali. Brief discussion on the biology and life cycle of M. mali is given. An overview of all known hosts and the possible distribution of M. mali in Europe are also presented. [ABSTRACT FROM AUTHOR]

Meloidoderita salina sp. n. is described and illustrated from the halophytic plant Atriplex portulacoides L. (sea purslane) growing in a micro-tidal salt marsh in the Mont-Saint-Michel Bay in France. This new species is the first member of Meloidoderita Poghossian, 1966 collected from a saline environment, and is characterized by the following features: sedentary mature females having a small swollen body with a clear posterior protuberance; slightly dorsally curved stylet, 19.9 μm long, with posteriorly sloping knobs; neck region irregular in shape and twisted; well developed secretory-excretory (S-E) pore, with markedly sclerotized S-E duct running posteriorly; prominent uterus bordered by a thick hyaline wall and filled with eggs. The adult female transforms into a cystoid. Eggs are deposited in both egg-mass and cystoid. Cystoids of Meloidoderita salina sp. n. display a unique sub-cuticular hexagonal beaded pattern. Male without stylet, pharyngeal region degenerated, S-E duct prominent, deirids small, developed testis 97.5 μm long, spicules 18.4 μm long, cloacal opening ventrally protruded, small phasmids posterior to cloaca opening and situated at 5.9 (3.2-7.7) μm from tail end, and conical tail ending in a rounded terminus marked with one (rarely two) ventrally positioned mucro. Additionally, some young males of the new species were observed enveloped in the last J2 cuticle. Second-stage juvenile body 470 μm long, with a 16.4 μm long stylet, prominent rounded knobs set off from the shaft, hemizonid anterior and adjacent to S-E pore, small deirids located just above S-E pore level, genital primordium located at 68-77% of body length, phasmids small and located at about 19 μm from tail tip, and tail 38.7 μm long, tapering to finely pointed terminus with a finger-like projection. Phylogenetic analyses based on the nearly full length small subunit ribosomal DNA sequences of Meloidoderita salina sp. n. revealed a close relationship of the new species with Sphaeronema alni Turkina & Chizhov, 1986 and placed these two species sister to the rest of Criconematina. [ABSTRACT FROM AUTHOR]

Holo and paratypes of the root-knot nematodes Meloidogyne mayaguensis Rammah & Hirschmann, 1988 and M. enterolobii Yang & Eisenback, 1983 were morphometrically and morphologically compared. All observed female, male and second-stage juvenile morphometrical and morphological characters are identical for the two studied species. Additionally, contradictions between the original species descriptions were unravelled. The present study of holo- and paratypes confirms the taxonomical status of Meloidogyne mayaguensis as a junior synonym for M. enterolobii. [ABSTRACT FROM AUTHOR]

Eleven golf courses and eight football pitches, located in Belgium, were surveyed for plant-parasitic nematodes. This revealed a remarkably high diversity: 52 different species/taxa were identified morphologically, belonging to 23 genera and nine families. Among the most prevalent nematodes on both sports field types were Helicotylenchus pseudorobustus and Meloidogyne naasi (>85% and >45% of the analysed samples, respectively). Golf greens contained a higher density and diversity of cyst nematodes than football fields. Cyst nematode species included Punctodera punctata, Heterodera mani, H. ustinovi, H. bifenestra and H. hordecalis. Multivariate statistics of the first three species showed that they could be separated based on morphometrical characters of juveniles, but not on values based on the vulval pattern. Several detected species, e. g., Meloidogyne minor, are a potential source of infestation of agricultural fields. This study shows the importance of plant-parasitic nematodes in turf grass in temperate Europe. In addition, a comparison between two extraction methods revealed that significantly more nematodes were extracted with the zonal centrifuge than after 2 weeks extraction with the Baermann method, except for juveniles of Meloidogyne spp. and cyst-forming species. [ABSTRACT FROM AUTHOR]

Apratylenchinae subfam. n. is proposed within the Pratylenchidae to include Apratylenchus gen. n. and two new species, A. vietnamensis gen. n., sp. n. and A. binhi gen. n., sp. n., from coffee plantations in Vietnam. Apratylenchus gen. n. is distinguished by the presence of transverse rows of cuticular tubercles on the annuli and by sexual dimorphism in which the males are stout and cylindrical, but mature sedentary females are club-shaped. The sedentary females are broadest in the posterior third although narrowing posterior to the vulva (V ≥ 85%). The female cephalic region is low and dome-shaped with all labial sectors fused to one another and the oral disc and the pharyngeal glands overlap the intestine ventrally. Males have a weak stylet with reduced knobs and a conical tail with a blunt terminus, arcuate spicules and a non-protrusible gubernaculum. Apratylenchus vietnamensis gen. n., sp. n. is characterised by a sedentary mature female with a 368-515 μm long club-shaped body, cephalic region low, dome shaped with three annuli, body annuli bearing a single or double row of refractive tubercles, stylet 17.0-19.9 μm long, V = ca 88-92, spermatheca filled with sperm and males known, if rarely found, in the type population. Males have a weak, 15 μm long stylet with reduced knobs, 16 μm spicules, a non-protrusible gubernaculum and low bursa. It differs from A. binhi gen. n., sp. n., the only other nominal species of the new genus, by longer female body (368-515 vs 326-364 μm), longer distance from anterior end to anus (353-512 vs 310-348 μm) and longer stylet (17.0-19.9 vs 14.7-16.9 μm). In addition, the spermatheca is filled with round sperm vs empty in A. binhi gen. n., sp. n. and the cuticle has less densely spaced and less pronounced tubercles. D2/D3 sequences of the 28 rDNA gene clearly support the separation of Apratylenchus gen. n. from other Pratylenchidae and further distinguish the two new species from each other. [ABSTRACT FROM AUTHOR]

A root-knot nematode parasitising yakon (Polymia sonchifolia) in São Paulo State, Brazil, is identified as Meloidogyne inornata. The species is redescribed from this material and compared with the original description of M. inornata. The female perineal patterns have a distinct, high, dorsal arch composed of smooth to wavy striae, similar to Meloidogyne incognita. The female stylet is 15.0-17.0 μm long with the cone generally slightly curved dorsally and with well developed knobs. DGO is 3.5-4.5 μm. Males have a high, rounded, head cap that is continuous with the body contour and has a large, round, centrally concave, labial disc raised above the medial lips. The head region is never marked by incomplete annulations and the stylet is robust, 20.0-25.0 μm long, with a straight cone, cylindrical shaft with several small projections and pear-shaped, backwardly sloping knobs. The stylet length of second-stage juveniles is 10.0-13.0 μm, DGO is 2.5-3.5 μm, tail length is 35.0-58.0 μm and c = 6.7-13.9. Biochemically, the esterase phenotype I3 (= Y3) is species-specific and is the most useful character for differentiating M. inornata from other Meloidogyne species. Reproduction is by mitotic parthenogenesis, 3n = 54-58. In a soybean test, cv. Abura was susceptible and cv. LA411219 was highly resistant. As the type material is lost, a neotype female is formally designated. [ABSTRACT FROM AUTHOR]

Pin nematodes of the genus Paratylenchus are obligate ectoparasites of a wide variety of plants that are distributed worldwide. In this study, individual morphologically vouchered nematode specimens of fourteen Paratylenchus species, including P. aculentus, P. elachistus, P. goodeyi, P. holdemani, P. idalimus, P. microdorus, P. nanus, P. neoamblycephalus, P. straeleni and P. veruculatus, are unequivocally linked to the D2-D3 of 28S, ITS, 18S rRNA and COI gene sequences. Combined with scanning electron microscopy and a molecular analysis of an additional nine known and thirteen unknown species originating from diverse geographic regions, a total of 92 D2-D3 of 28S, 41 ITS, 57 18S rRNA and 111 COI new gene sequences are presented. Paratylenchus elachistus, P. holdemani and P. neoamblycephalus are recorded for the first time in Belgium and P. idalimus for the first time in Europe. Paratylenchus is an excellent example of an incredibly diverse yet morphologically minimalistic plant-parasitic genus, and this study provides an integrated analysis of all available data, including coalescence-based molecular species delimitation, resulting in an updated Paratylenchus phylogeny and the corrective reassignment of 18 D2-D3 of 28S, 3 ITS, 3 18S rRNA and 25 COI gene sequences that were previously unidentified or incorrectly classified. [ABSTRACT FROM AUTHOR]