Electrophoretic and hybridization comparison of Glossina morsitans morsitans, G. m. centralis, and G. m. submorsitans (Diptera: Glossinidae)
Two colonies of Glossina morsitans morsitans Westwood, two colonies of Glossina morsitans submorsitans Newstead, and one colony of Glossina morsitans centralis Machado, each originating from a different geographic location, were compared genetically and by their ability to hybridize. There were marked asymmetries in results of intersubspecific hybridization. Most F1 males were sterile but most F1 females were fertile. Nei's mean genetic identity (based on 12 loci) and four hybridization indices (based upon proportion of females fertilized, puparia produced per fertilized female, F1 adults per fertilized female, and proportion of females fertilized in backcross experiments) yielded the same results: intrasubspecific similarities are greater than intersubspecific similarities, and G. m. centralis is more similar to G. m. morsitans than it is to G. m. submorsitans. Evidence is presented indicating that a phenogram based upon allele frequencies is as good as phenograms based upon hybridization as a means of representing relationships among tsetse flies.