Open Access. The Published version of this work has been reproduced here with the permission of the Entomological Society of America.
This article is the copyright property of the Entomological Society of America and may not be used for any commercial or other private purpose without specific written permission of the Entomological Society of America. This work was published in American entomologist, 55(4): 250-257, 2009. To view the published open abstract, go to http://dx.doi.org/10.1093/ae/55.4.250 (Please note: access via this link may only be available with a subscription).