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  • Author or Editor: Xinxin Ma x
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Summary

Cryptaphelenchus recticaudatus n. sp. is described and illustrated in Pinus elliottii from the USA. The new species is characterised by the female body 310-431 μm long with distinctly annulated cuticle, lateral fields with four lines, lip region separated from the body by a shallow depression, delicate stylet with small knobs, post-vulval uterine sac short, and rectum and anus invisible. Males are 228-314 μm long, spicules 9.8-12.4 μm long with a well-developed and broad condylus, and seven caudal papillae arranged as a single (P1) and pair (P2) of precloacal papillae plus two pairs of postcloacal papillae. Based upon the general female morphology, the new species most closely resembles C. baujardi and C. iranicus. The morphological differences with the aforementioned species and other species of the genus are discussed. The phylogenetic analyses based on small (SSU) and large subunit (LSU) D2-D3 expansion segments of ribosomal DNA of different individuals of the new species revealed that the new species fell into the Cryptaphelenchus clade in both SSU and LSU trees. The monophyly of the genus was retained after adding newly generated sequences of the new species.

In: Nematology

Summary

Ruehmaphelenchus americanum n. sp., isolated from southern yellow pine (Pinus taedae L.) from the USA is described and figured. It is characterised by a relatively stout body (a = 30 for females and males), three lines in the lateral field, both oocytes and spermatocytes arranged in two rows, male spicules relatively small (14-18 μm) with weakly developed condylus and rostrum, short tail with a bluntly pointed tip, seven papilliform genital papillae present, female vulva positioned at ca 82% of body length, vulval lips slightly protruding, post-uterine branch extending two-thirds of vulva to anus distance, tail cylindrical, ca two anal body diam. long, terminus forming a spike-like projection or mucron, 7.6-12.2 μm long, with pointed tip. The new species can be separated from 11 known species (except R. thailandae) by male genital papillae arrangement (the second and third pair adjacent vs separated). Detailed phylogenetic analysis based on 18S and 28S D2-D3 region ribosomal RNA (rRNA) sequences has confirmed the status of this nematode as a new species.

In: Nematology

Summary

Bursaphelenchus paraleoni n. sp. was isolated from Loblolly pine, Pinus taeda, logs from the USA. The new species is characterised by a lateral field with three lines, 13-16 μm long stylet with small basal swellings, and the excretory pore located slightly posterior to the nerve ring. The male spicules are mitten-shaped, the lamina smoothly tapering towards the distal tip. The condylus is broadly rounded, with a small dorsally bent hook, rostrum triangular or conical with finely rounded tip, and cucullus absent. One midventral precloacal papilla, one adcloacal pair and two postcloacal pairs of genital papillae are present. The bursal flap is long and spade-like with the posterior margin truncate or irregular. Females have a small vulval flap 4-6 μm long, a post-vulval uterine sac extending for 34-49% of the vulva to anus distance, a very long tail with slight ventral curvature, mostly filiform and with a finely rounded terminus, occasionally bluntly rounded. Huge variation in the tails of males and females were observed in a culture. It is similar to species of B. eidmanni, B. leoni, and B. silvestris in the leoni-group but detailed phylogenetic analysis based on 18S, ITS and D2-D3 28S sequences confirmed it as a new species.

In: Nematology

Summary

Ruehmaphelenchus taedae n. sp., isolated from Loblolly pine logs (Pinus taedae L.) from the USA, is described and figured. It is characterised by a relatively slim body (a = 42 and 43 for males and females, respectively), three lines in the lateral field, male spicules relatively small (12-18 μm) with high and dorsally bent condylus and weakly developed rostrum, bursal flap absent, short tail possessing a long terminal spike ending in a bluntly rounded tip and 8.7-13.3 μm long, vulva positioned at ca 83% of body length, vulval flap absent, vulval lips slightly protruding, post-vulval uterine branch extending for less than half of vulva to anus distance, and female tail conoid, ca 3-4 anal body diam. long, with 13.7-18.5 μm terminal projection. The new species can be separated from all other species of the genus by the male tail possessing a long terminal spike and the more anterior excretory pore. Detailed phylogenetic analysis based on 28S D2-D3 region sequences confirmed the status of this nematode as a new species.

In: Nematology

Summary

Ektaphelenchoides compsi is redescribed morphologically with new molecular characterisation. It was isolated from a dead Pinus massoniana tree in Ningde City, Fujian Province, China. Detailed morphology of the spicule, female gonad, hemizonid position, arrangement of male caudal papillae and female tail terminus shape are documented. It is characterised by a lateral field with three lines (forming two bands), tripartite stylet 17.8 (17.0-19.4) μm long without basal thickenings, metacorpus rectangular with anterior 40% granular and posterior part weakly muscular, metacorpal valve slightly posterior to middle of metacorpus, excretory pore at level of nerve ring, vagina with thickened walls and strongly developed muscular bundles, vulval lips slightly protuberant, vulval flap absent, distal region of post-vulval uterine sac appearing as a weakly developed oogonia, anus and rectum indistinct, female posterior part (‘tail’) dorsally convex, conical, terminal region contracted into a bluntly pointed tip. The spicules are arcuate, 15.6 (14.3-16.3) μm along the chord, lamina smoothly curved to distal end, capitulum slightly concave, condylus well-developed with broadly rounded tip and slightly depressed at dorsal end, rostrum triangular with finely rounded tip, cucullus absent, and with seven caudal papillae present. The near full length 18S and 28S D2-D3 regions of rRNA genes sequences were characterised. The phylogenetic analyses revealed that the Fujian population of E. compsi grouped with the Zhejiang population of E. compsi, both being morphologically identical.

In: Nematology

Summary

Bursaphelenchus taedae sp. n. of the eggersi-group was detected in loblolly pine logs from the USA together with B. antoniae. It is characterised by a relatively small stylet with basal swellings, a lateral field with three lines, and the excretory pore located at the level of the nerve ring. The female has a very small extension of the anterior vulval lip over the vulva (= a ‘vulval flap’), a long PUS extending for 40.1-67.8% of vulva to anus distance, and hook-like tail conical, gradually tapering to a finely rounded or broadly rounded terminus. The male spicules are 17-22 μm long in chord, only slightly ventrally curved, condylus short, truncate, slightly dorsally bent to dorsally hooked, rostrum ca 3-4 μm long, close to the proximal spicule end, without cucullus. Seven genital papillae present. Bursaphelenchus taedae sp. n. can be distinguished from other species of the eggersi-group by morphological and molecular characters.

In: Nematology

Summary

Bursaphelenchus parayongensis n. sp. was isolated from packaging wood of a consignment from China exported to Germany. The new species is characterised by the lateral field with three lines, 9-13 μm long stylet with small basal swellings, and the excretory pore located near the posterior part of metacorpus. The male spicules are mitten-shaped, the lamina smoothly tapers towards the distal tip. The condylus is broadly rounded, with a small dorsally bent hook, rostrum triangular with sharply pointed tip, and without cucullus. One precloacal papilla, one adcloacal pair and two postcloacal pairs of male papillae present, with the posteriormost pair forming ‘gland papillae’. Bursal flap long, spade-like with posterior margin truncate or irregular. Females have a small vulval flap of 2-3 μm long, and a post-vulval uterine sac extending for 55-77% of the vulva to anus distance. Tail cylindrical, mostly (about 70%) with a robust mucron, very short to less than 3 μm, but occasionally tail terminus bluntly rounded, without mucron. It is similar to species in subgroup 3 of the eggersi group including B. carpini, B. clavicauda, B. cryphali and B. yongensis, but morphologically different. Detailed phylogenetic analysis based on partial 18S, ITS and D2-D3 region of 28S sequences has confirmed the status of this nematode as a new species.

In: Nematology

Summary

Understanding the occurrence and distribution of parasitic nematodes is crucial – some are economic pests, and some are important predators of their insect associates. In our recent nematode inventory survey, two populations of an ektaphelechid nematode were detected in the branches of Pinus trees; later the same nematode population was detected in plant quarantine examinations of wood packaging material imported from Japan. The species was processed and identified as Ektaphelenchoides diversislocis sp. n. The new species can be characterised by having three lateral lines, stylet long and tripartite, excretory pore at the level of nerve ring, comparatively longer post-vulval uterine sac, indistinct rectum and anus. Female posterior body region conical, gradually narrowing, like a mucron or filiform. Male spicule with well-developed condylus, triangular rostrum, and cucullus absent. The species is morphologically and molecularly close to E. compsi. The new species was characterised with near full-length 18S, 28S D2-D3 regions, and internal transcribed spacer (ITS) rRNA genes and mitochondrial cytochrome oxidase I (COI) gene sequences. The species within the Ektaphelenchoides genus are considered to have predatory roles against insect associates; therefore, the discovery of E. diversislocis sp. n. from local and foreign woodlands warrants increased sampling and research attention.

In: Nematology