First report and characterization of Deladenus proximus (Nematoda: Neotylenchidae) associated with Sirex nigricornis (Hymenoptera: Siricidae) in Canada.
Yu, Q., de Groot, P., Leal, I., Davis, C., Ye, W., and Foord, B. (2012). "First report and characterization of Deladenus proximus (Nematoda: Neotylenchidae) associated with Sirex nigricornis (Hymenoptera: Siricidae) in Canada.", International Journal of Nematology, 21(2), pp. 139-146.
A Deladenus species, new to Canada was discovered from a native wood wasp species Sirex nigricornis in Ontario, Canada. The identity was confirmed with morphological and molecular methods as D. proximus Bedding 1974. A sphaerulariid form of female reproducing ovoviviparously was found within the haemocoel of the insect adults; the nematode juveniles were reared on isolates of the symbiotic fungus Amylostereum chailetti for the mycophagous form of the nematode, and the pre-adult infective females were induced from those mycophagous nematodes. The morphology and morphometrics of the mycophagous form and pre-adult infective form matched with D. proximus. The excretory pore of the mycophagous female was located at 134.23-150.89 µm from the anterior end of the nematode, and 2.21-11.14 µm anterior to the hemizonid. The 18S and ITS genes of ribosomal DNA were PCR amplified and sequenced. This species was in a well-supported clade together with D. siricidicola in a phylogeny tree based on the 18S sequences. This is the first report of D. proximus in Canada, and the first molecular characterization of the species.