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Summary

Acrobeles aenigmaticus sp. n. is described from the North-West District (Ngamiland) of Botswana, which forms part of the Kalahari Desert. This new species is characterised by its body length, ‘double’ cuticle bearing numerous interannular punctations, lateral fields with two longitudinal incisures, lips triangular bearing triangular tines with variation in their morphology, labial probolae bifurcated with prongs bearing triangular tines, pharyngeal corpus 2.8-3.8 times the isthmus length, spermatheca 0.8-1.8 times the body diam., post-vulval sac 1.3-2.2 times the body diam., vagina bent to the left side, vulva located left subventral and very reduced, female tail conoid-elongate, male tail conoid, spicules 24-29 μm and gubernaculum 13-17 μm in length. Molecular characterisation of 18S and 28S rRNA shows the relationship of this species with other species of Acrobeles that also present a ‘double’ cuticle, as well as with other cephalobids (e.g., Cervidellus alutus) with the same characteristic in terms of its cuticle.

In: Nematology

Summary

Aphelenchoides tabarestanensis n. sp. was isolated during a survey of nematodes associated with bark samples of pine trees (Pinus brutia) in Mazandaran province, northern Iran. The new species is characterised by body length of 656 (580-786) μm (females) and 490 (480-500) μm (males), weakly annulated cuticle, four lines in the lateral field, and an offset lip region. The stylet is 10.5 (10-11) μm long and has small basal swellings. The excretory pore is located at nerve ring level and the hemizonid was not seen. The post-vulval uterine sac is 40.8 (38-43) μm long, the spicules are relatively short (18-19 μm in dorsal limb), and the male tail has the usual three pairs of caudal papillae (2 + 2 + 2). The female tail is subcylindrical with two or three minute processes at the tip. The new species belongs to the Group 3 category of Aphelenchoides species and is close to seven known species of the genus, namely: A. asteromucronatus, A. besseyi, A. fujianensis, A. goodeyi, A. ritzemabosi, A. siddiqii, and A. stellatus, but differs by body size, shape of tail mucron, stylet length, size of spicules, and length of post-vulval uterine sac. Phylogenetic analysis based on small subunit (SSU) and partial large subunit (LSU) sequences of rRNA supported the morphological results.

In: Nematology

Summary

Basilaphelenchus brevicaudatus n. sp., the third species of this apparently rare genus, is described and illustrated. It was recovered from wood and bark samples from a dead forest tree in the Golestan province of northern Iran. It is typologically characterised by female body length (448 (365-492) μm), three lines in the lateral fields, raised cephalic region having a sclerotised vestibule and cephalic framework, stylet thin with delicate conus and thicker shaft, both parts lacking a visible lumen, and with three elongate, backwardly directed knobs, small, spherical to spade-shaped metacorpus with small, posteriorly located valve (at 72 (58-74)% of metacorpus length), simple vulva without flap at 72.5 (69-78)% of body length, post-vulval uterine sac 32.4 (29.0-37.0) μm long, functional rectum and anus, female tail conical, short (c′ = 2.6 (1.9-3.3) in female, and 2.5 (2.3-2.8) in male), dorsally convex and ventrally concave with blunt end or having a small mucron, both forms with a hyaline-like tip. Males common, with well-curved 9.2 (9.0-10.5) μm long spicules measured along the mid-line, three pairs of small caudal papillae (lacking the single P1 ventral papilla) and no bursa at tail tip, but with hyaline region, similar to females. Basilaphelenchus brevicaudatus n. sp. is compared with the two currently known species of the genus, the type species, B. persicus, and B. grosmannae. Molecular phylogenetic inferences using partial sequences of small and large subunit ribosomal RNA genes (SSU and LSU) from different isolates of the new species revealed that it belongs to the Tylaphelenchinae clade.

In: Nematology

Summary

A new species of Bursaphelenchus, extracted from unprocessed logs of Milicia excelsa from Cameroon and arriving in the port of Leghorn, Tuscany, Central Italy, is described. Bursaphelenchus irokophilus n. sp. is based upon morphological and molecular characters and is characterised by the two-lined lateral field, mitten-shaped spicule possessing cucullus and well-developed and slightly dorsally curved condylus with narrowly rounded tip, female vulva with side flap, and long, smoothly tapering and strongly ventrally recurved female tail. The new species belongs to the abietinus-group and is similar to, but distinguished from, B. abietinus and B. rainulfi by the position of secretory-excretory pore, longer and slender female tail and some morphometric values. In addition, the phylogeny based on SSU and D2-D3 LSU regions shows that this species belongs to the abietinus-group, the relationship among the species of this group being discussed.

In: Nematology

Summary

Bursaphelenchus rockyi n. sp., isolated in Peking, China, from peat moss imported from Russia, is described. It is characterised by a lateral field with four lines, excretory pore located at the base of the nerve ring or slightly posterior, spicule 15.9 (15.1-17.3) μm long along the chord and with high condylus and a rounded tip, rostrum triangular or conical with bluntly pointed tip, lamina curvature becoming more pronounced at 60% of total length, six caudal papillae with P3 and P4 adjacent to each other, bursa small, starting posterior to P4, vulval lips hemispherical and protruding, and tail conical with finely rounded or mucronated terminus. The new species belongs to the fungivorus-group and is most similar to B. arthuri, B. arthuroides, B. fungivorus and B. seani, but can be distinguished from related species by morphological and sequencing results.

In: Nematology

Summary

Discocriconemella sinensis n. sp. isolated in Hangzhou, Zhejiang, China, from the rhizosphere of Camellia sinenis is described. The new species was characterised morphologically and molecularly. Important morphological details were elucidated by SEM photographs. The new species is characterised by an uninterrupted rounded cephalic disc, en face showing a rectangular labial plate with slit-like oral apertures, labial plate surrounded by slightly elevated projections resembling rudimentary lobes, R = 66 (64-69), Rex = 21 (17-24), stylet 74 (67-81) μm long, excretory pore located at the base of the pharyngeal bulb, vulva open, tail short and conoid with a lobed terminus. The species belongs to the group 1 lip pattern. Morphologically, it is most similar to D. discolabia, D. mauritiensis, D. mineira and D. perseae. This is the first new Discocriconemella species described from China. Phylogenetic analyses based on analysis of the D2-D3 expansion segments of the 28S rRNA, ITS rRNA, partial 18S rRNA, and COI gene revealed that the new species formed a separate clade from other criconematid species, thereby supporting its status as a new species of the genus. The new species showed close relationships with Criconemoides informis.

In: Nematology

Summary

Ektaphelenchus cupressi n. sp. was isolated during a survey of nematodes associated with bark samples of a dead cypress tree (Cupressus sempervirens) in Mazandaran province, northern Iran. The new species is characterised by a female body length of 612 (520-693) μm, stylet 17-19 μm long with wide lumen and lacking basal swellings, head region hemispherical in lateral view and slightly offset from the body contour by a shallow constriction, three incisures in the lateral field, excretory pore situated anterior to level of metacorpus valve, hemizonid not seen, post-uterine sac 29-35 μm long, shape of the tail terminus, and arrangement of the male caudal papillae. By a combination of morphological characters, e.g., stylet without knobs or swellings at the base, short conical tail, PUS length, and only a vestigial anus and rectum in most individuals, the new species shares similarities with species belonging to three genera, i.e., Anomyctus, Ektaphelenchus, and Seinura. Phylogenetic analysis based on small subunit (SSU) and partial large subunit (LSU) sequences of rDNA confirmed its status as a new species.

In: Nematology

Summary

In this study, we describe Labrys fuzhouensis sp. n. based on detailed morphology revealed by scanning electron microscopy and molecular data inferred from 18S and 28S rRNA. The new species differs from other Labrys species by a combination of several morphometric and morphological characters: vulva-anus distance 66-74 μm, tail length 172-182 μm, post-uterine sac 11-12 μm, excretory duct less sclerotised, and hexagon-shaped labial disc. The novelty of L. fuzhouensis sp. n. is also confirmed by multi-dimensional scaling analysis. The 18S and 28S rRNA-based phylogenies suggest that the new species nested in the Labrys clade as sister to L. chinensis. In addition to the new species description, Coslenchus rafiqi is reported from China for the first time, the description being supplemented by the first molecular data (18S and 28S rRNA) for this species.

In: Nematology

Summary

Longidorus barsii sp. n., from Mt Tara in the Balkan Peninsula, is described and characterised by using a polyphasic approach. The species has numerous males. The female body is 5-7 mm long, rather stout and resembles a large Xiphinema. The lip region is wide, with rounded sides continuous with the neck, frontally flattened and depressed around the oral aperture, amphids are pouch-like and distinctly bi-lobed and the odontostyle is moderately long. The nuclei of the pharyngeal glands are in the normal position, the dorsal nucleus located somewhat posterior to anterior third of bulb. The uteri are long, the distal inner epithelium densely covered with papilla-like outgrowths. The tail is rounded, bluntly conoid and very short. Alpha-numerical identification codes: A4/5, B45, C3, D3, E2, F3, G 1(2), H1, I2, J1, K67. The morphologically most similar species are L. kheirii, L. polyae and L. profundorum. Additional observations are provided on the anterior body region and genital organs in L. barsii sp. n., L. piceicola, L. silvae, and L. uroshis. Selected features are discussed from the taxonomic and functional points of view. The D2-D3 expansion domains of the 28S rRNA gene and the ITS region of L. barsii sp. n. were amplified and sequenced. Phylogenetic analysis using the D2-D3 expansion domains of the 28S rRNA gene revealed close evolutionary relationships with L. polyae, L. athesinus and three unidentified Longidorus spp.

In: Nematology

Summary

Pasteuria penetrans is a hyperparasite with potential as a biological control agent of root-knot nematodes, Meloidogyne spp. In this study two exotic Pasteuria isolates (PP-3 and PP-J) were developed on different Meloidogyne spp. collected from different districts of Punjab, Pakistan. The development of PP-3 and PP-J on different field populations of Meloidogyne spp. showed differential infectivity in terms of nematode reproduction variables. The development of PP-3 and PP-J was maximum on tomato as compared to cucumber. It was probably due to more invasion sites for nematodes present in the tomato roots. However, a bigger root system has not always been a guarantee for development of Pasteuria on Meloidogyne spp. For successful development of Pasteuria, the key parameters are the percentage of infected females, number of endospores (female)−1 or endospores (mg root powder)−1. The results of these parameters are greater in tomato as compared to cucumber.

In: Nematology