Abstract
The coleopteran family Curculionidae is one of the most important vector and/or host insect groups for entomogenous nematodes in the world. The bark beetles are members of the subfamily Scolytinae and appear to be a very suitable host/vector group for the nematodes, i.e., more than 100 species of parasitic and/or phoretic nematodes have been described from this group. Contrastingly, only seven nominal species have been recorded from the ambrosia beetles and the rest of the Scolytinae and Platypodinae, which are closely related to the bark beetles. Thus far, there is no clear explanation for the differences in nematode diversity between the bark and the ambrosia beetles. The life cycle and habitat environmental conditions do not differ that much between these two beetle groups. However, some nematode groups, e.g., the genus Ruehmaphelenchus, have been isolated only from the ambrosia beetles, and are hypothesized to be specific to them. Most of the current studies on bark and ambrosia-beetle associated nematodes are descriptive. Understanding the stenotrophic relationships between ambrosia-beetles and their associated nematodes and the evolutionary implications of these interactions will require experimental studies and more extensive descriptive survey work in the future.
