A Redescription of the Bark Beetle Nematode Contortylenchus brevicomi: Synonym Contortylenchus barberus (Nematoda : Sphaerulariidae).

Contortylenchus barberus is synonymized with C. brevicomi because their original separation was based on minor morphometric variations that are considered here to be intraspecific rather than interspeciflc. The ranges of body length and body width in measured specimens of C. brevicomi encompass those of the original description of C. brevicomi and C. barberus. The presence or absence of the caudal mucro is considered not a valid criterion for species differentiation. Several of the morphometric details of the two species overlap and thus are not considered suitable for species differentiation. Such variation may be due to stresses of the host-parasite relationship. The respective hosts of the two nematodes, Dendroctonus brevicomis and D. barberi, have been synonymized into the former species. The description of the larval stages of C. brevicomi is presented.