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1990s

a Based in part on Norris et al. (2003).

a Based in part on Norris et al. (2003).

on information for these two species, it is possible to infer that the other species in the genus share at least some of the following features: eggs are laid in the soil adjacent to growing leguminous plants; larvae feed on nitrogen-fixing root nodules and pupate in soil inside pupal cases; first-generation adults emerge when seedlings emerge, and second-generation adults emerge when plants are in full vegetative growth, feeding first on foliage and, later on, switching to feeding on developing pods. The biosystematic information on the genus allows students of agricultural entomology in South, Central, or

CareWmi srcuùia CmUam» tn/unali

FIGURE 2 Morphological diversity and biological similarities in the genus Cerotoma: four of the dozen known species are illustrated by male and female specimens. The species are clearly distinguishable by morphological characters, but they have similar life histories and behaviors. (From unpublished drawings by J. Sherrod, Illinois Natural History Survey.)

CareWmi srcuùia CmUam» tn/unali

FIGURE 2 Morphological diversity and biological similarities in the genus Cerotoma: four of the dozen known species are illustrated by male and female specimens. The species are clearly distinguishable by morphological characters, but they have similar life histories and behaviors. (From unpublished drawings by J. Sherrod, Illinois Natural History Survey.)

North America to understand, at least in general terms, the role of any other species of Cerotoma within their particular agroecosystem.

The flip side of this notion is recognition that closely related and morphologically nearly undistinguishable (sibling) species may have many important biological differences. Examples of the critical need for reliable biosystematics studies are found in the biological control literature. The present account is based on studies conducted by Paul DeBach, one of the leading biological control specialists of the twentieth century. The California red scale, Aonidella aurantii, is a serious pest of citrus in California and other citrus-producing areas of the world. Biological control of the red scale in California had a long history of confusion and missed opportunities because of misidentification of its parasitoids. The red scale parasitoid Aphytis chysomphali had been known to occur in California and was not considered to be a very effective control agent. When entomologists discovered parasitized scales during foreign exploration, the parasitoids were misidentified as A. chrysomphali and therefore were not imported into California. It was later discovered that the parasitoids were in fact two different species, Aphytis lingnanensis and A. melinus, both more efficient natural enemies of the California red scale than A. chrysomphali. Now A. lignanensis and A. melinus are the principal red scale parasitoids in California. Further biosystematics studies have shown that what was once thought to be single species, A. chrysomphali, parasitic on the California red scale in the Orient and elsewhere, and accidentally established in California, is in fact a complex including at least seven species having different biological adaptations but nearly indistinguishable morphologically.

Knowledge of the name of a species, however, is not an indication of its true potential economic impact or pest status. A next important phase in agricultural entomology is, therefore, the assessment of benefits or losses caused by that species.

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