Gonatocerus ashmeadi Girault is a common and seemingly widespread egg parasitoid of glassy-winged sharpshooter (GWSS). Location records for G. ashmeadi indicate its natural range to be Florida, Georgia, Louisiana, northeastern Mexico, Mississippi, North Carolina, South Carolina, southern and eastern Texas (which coincides with the presumed native range of GWSS), and southern and central California (the adventive range of GWSS). The purpose of our work is to determine whether G. ashmeadi in the native range of GWSS is one species or a complex of cryptic species that can’t be separated on the basis of currently employed morphological characters. We are using three approaches to determine the species identity of different G. ashmeadi populations: (1) mating compatibility studies to determine if different populations of G. ashmeadi are reproductively isolated, or if mating occurs, whether offspring are viable thereby defining species groups on the basis of successful interbreeding; (2) reassessment of key morphological features using scanning electron microscopy (SEM) to determine if subtle morphological differences exist between G. ashmeadi populations which could possibly indicate species differences; (3) genetics studies to determine if molecular differences exist between G. ashmeadi populations collected from different regions by comparing mitochondrial and ribosomal DNA sequences. Molecular dissimilarities of key regions could potentially indicate the existence of different species. Results from these three areas (behavior, morphology, and molecular) of investigation will be evaluated together to determine whether G. ashmeadi as it is currently viewed is a valid species or whether it is an aggregate of morphologically indistinguishable cryptic species.
Species 1: Hymenoptera Mymaridae Gonatocerus ashmeadi
Species 2: Homoptera Cicadellidae Homalodisca coagulata (glassy-winged sharpshooter)
Keywords: biological control
Back to Display Presentations, Section Ca. Biological Control
Back to Posters
Back to The 2003 ESA Annual Meeting and Exhibition