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  • Author or Editor: Yiwu Fang 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

Pseudaphelenchus zhoushanensis n. sp. was isolated from a dead Pinus thunbergii at Changgang Mountain, Zhoushan Islands, Zhejiang Province, China. It is characterised by the small to medium length body, cuticle slightly annulated, presence of three lateral lines, stylet 9.0-10.7 μm with small but conspicuous basal knobs, excretory pore located from same level as the metacorpus to slightly anterior to metacorpus, true bursa surrounding entire tail but inconspicuous, male tail conical with a single mucron, spicule with distinct condylus and rostrum strongly arcuate to a pointed end, female tail conical with annulation, strongly ventrally bent in distal part of tail, with terminus bluntly pointed or finely mucronate. Phylogenetic analyses using sequences of the18S and 28S D2-D3 regions of rDNA confirmed the status of P. zhoushanensis n. sp. as a new species. Combining the molecular phylogenetic analyses, morphology and biology of P. zhoushanensis n. sp. and Tylaphelenchus jiaae indicates that T. jiaae is a member of Pseudaphelenchus to which it is herein transferred as P. jiaae n. comb. (= T. jiaae).

In: Nematology

Bursaphelenchus parapinasteri is redescribed morphologically and with new molecular characterisation. It was isolated from a dead Pinus thunbergii on Changgang Mountain, Zhoushan Islands, Zhejiang Province, China. Detailed morphology of the spicule, female gonad, hemizonid position, arrangement of male caudal papillae, and female tail terminus shape are documented. The ITS-RFLP patterns and the ITS1/2, partial 28S D2-D3 and partial 18S gene sequences were characterised. The phylogenetic analyses revealed that B. parapinasteri belongs to the hofmanni-group sensu Braasch and is close to B. anamurius, B. hofmanni, B. mazandaranense, B. paracorneolus, B. pinasteri and B. ulmophilus. A diagnostic key to species of the hofmanni-group is presented.

In: Nematology

Ruehmaphelenchus quercophilus n. sp., isolated from a dying oak, Quercus robur, in the State Forests, Łopuchówko District, Poland, is described and figured. It is characterised by three lateral lines, relatively stout body, excretory pore posterior to nerve ring, five caudal papillae, spicules relatively small (12-14 μm) with weakly developed condylus and rostrum, bursa absent, vulva positioned at ca 78% of body length, vulval flap absent, post-uterine branch extending for slightly over half of vulva to anus distance, and conoid tail with a bend at the distal end forming a terminal projection 10-14 μm long. The new species is very similar to four other described species, namely R. formosanus, R. juliae, R. thailandae, and R. sirisus. Detailed phylogenetic analysis based on 18S, 28S D2-D3 and ITS 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

Bursaphelenchus decraemerae n. sp., isolated in Ningbo, China, from packaging wood made of Pinus sp. imported from the USA, is described. It is characterised by the lateral field with three lines, a stylet 10-12 μm long with small basal swellings, excretory pore located 4-12 μm posterior to median bulb, spicule small, ventrally arcuate with lamina gradually tapering to distal tip, rostrum triangular pointed to conical, condylus elongated with bluntly rounded tip, and cucullus minute, barely visible. There are seven caudal papillae arranged as a single ventral precloacal papilla, one adcloacal pair and two postcloacal pairs. The bursal flap is narrow and oval. A small vulval flap is present in lateral view of the female and the tail is conical, strongly ventrally curved with the terminus finely pointed and sometimes appearing like a mucron. The new species is characterised by morphological and molecular analysis and is close to B. gerberae and B. sakishimanus.

In: Nematology

New morphological, molecular and bionomic data are added to update the description of Bursaphelenchus crenati. The nematode was isolated from larval galleries and adults of the Greater ash bark beetle, Hylesinus crenatus Fabricius, present in bark of older trees of European ash, Fraxinus excelsior L., in Poland. Detailed female and male morphology are documented in this paper and compared with the original description. From ITS1/2, partial 28S D2-D3 and partial 18S sequences, ITS-RFLP patterns and morphological analysis, B. crenati is suggested to be temporarily placed into the sexdentati group, close to B. andrassyi, B. vallesianus, B. sexdentati, B. pinophilus, B. poligraphi, B. fuchsi, B. incurvus, B. piniperdae, and B. pityogeni. However, B. crenati can be distinguished from these species by the strongly ventrally curved body and the presence of three incisures in the lateral fields.

In: Nematology

Two Sheraphelenchus populations were isolated from pine wood packaging from Italy and onion bulbs from South Korea at Ningbo Port, China, respectively. The former, on the basis of morphology and molecular sequencing, is described as S. parabrevigulonis n. sp., which is characterised by a stylet length of 11 μm, three lines in the lateral field, excretory pore at level with, or slightly posterior to, nerve ring, V = 93.1, and spicules with long condylus and membrane-like rostrum in a shallow triangular shape. The species from onion, also on the basis of morphology and sequence data, was identified as S. sucus, which is characterised by a stylet length of 13 μm (erroneously stated to be ca 6 μm in the type description), excretory pore at level of, or posterior to, median bulb, and V = 80.9. The phylogeny trees based on rDNA 18S, 28S D2-D3 and ITS1/2 sequences revealed that S. parabrevigulonis n. sp. and S. sucus clustered into a clear clade and grouped with Bursaphelenchus species. The study enriched the taxonomic information of Sheraphelenchus and confirmed its status as an independent genus.

In: Nematology