ECOLOGY AND POPULATION BIOLOGY Flight Phenology of Sympatric Populations of Reticulitermes (Isoptera: Rhinotermitidae) in Northern California: Disparate Flight Intervals Indicate Reproductive Isolation Among Cuticular Hydrocarbon Phenotypes

The diurnal ßights of Reticulitermes spp. have been reported to occur in the spring and early fall in northern California. From the spring of 1994 until the fall of 2001, we collected hundreds of alates of Reticulitermes spp. cuticular hydrocarbon phenotypes CA-A/A and CA-D during ßights from multiple locations in the San Francisco Bay Area. As predicted, there were two ßight seasons: one in the spring from February to May and one in the fall from October to December. The ßights in the springweremadeonlybyphenotypesCA-A/A ; those in the fall exclusively includedphenotype CA-D.Thesedisparate ßight times indicate that reproductive isolation is complete andprovide further biological evidence that phenotypes CA-A and CA-A are variants of one taxon and are distinct from CA-D.