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Pine Wilt Nematode

Scientific Name
Bursaphelenchus xylophilus
Scientific Author
(Steiner & Buhrer)
(Nematoda: Tylenchida: Aphelenchoididae: Bursaphelenchinae)

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Diagnostic Images

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Diagnostic Images (9)
Diagnostic Notes

Diagnostic characters: (Dr Mike Hodda - CSIRO, Entomology)
High offset lips, stylet 12 to 14┬Ám long with small knobs, bursa present in adult males, spicules slender with cuculus [anvil-like tip - can be seen clearly on the photo of adult male tail], and vulval flap present in adult females.  A rounded tail was seen as an additional useful differentiating character applying to most populations of PWN.  However, some populations of PWN, particularly from North America, have a proportion of the population with mucronate tails, so this character should be used with caution.
A specimen must have ALL these characters to be B. xylophilus.  Each character occurs elsewhere in nematoda many times and in many different combinations.

See weblinks for more images of characters

Description of male:  Spicules large, uniquely arcuate, paired, with sharply pointed prominent rostrum; distal ends of spicules with typical disc-like expansions.  Tail arcuate, terminus pointed, appearing talon-like on lateral view, surrounded by short, oval caudal alae.  Seven caudal papillae, one adanal pair just pre-anal, single papilla just pre-anal centered; two post-anal pairs just before caudal alae origin.
Description of female:  Lip region high, offset with six lips.  Stylet with small basal swellings.  Esophageal glands slender, 3-4 body-widths long, overlapping dorsally.  Excretory pore opposite junction of esophagus and intestine, sometimes at level of nerve ring.  Hemizonid conspicuous, about two-thirds body width behind median bulb.  Ovary outstretched, oocytes usually in single file.  Post uterine sac long, extending three-fourths distance to anus. Tail subcylindrical, usually with broadly rounded terminus.


University of Nebraska - Lincoln  Nematology

Bursaphelenchus - Female similar to Aphelenchoides but some species have a cuticular flap extending posteriorly over the vulva. Male with rose-thorn to mitten-shaped spicules usually with an elongated apex and prominent rostrum; gubernaculum absent; tail terminus with a short bursa, two to three pairs of subventral caudal papillae also present.


See UC Davis weblink

More Information
Walker, K.
19/07/2006 05:23 AEST
Last Updated
21/10/2011 09:31 AEST
Walker, K. (2006) Pine Wilt Nematode (Bursaphelenchus xylophilus) Updated on 10/21/2011 9:31:13 AM Available online: PaDIL -
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