Seasonal distribution of the leafhopper Carneocephala floridana (Homoptera: Cicadellidae) in north Florida salt marshes

The leafhopper Carneocephala floridana Ball is a common inhabitant of the S alt marshes of north Florida. Although C. floridana is not usually economic ally important, increased agriculture and residential development in coasta l areas may result in this insect becoming a more common pest species. Carn eocephala floridana, like other members of this genus, is a likely vector o f Pierce's disease of grapes. This study documents the yearly distribution of C. floridana among its most common native host plants. Although C, flori dana was present during every month of the year, it reached its highest den sities during the spring and summer months on mixed herbaceous plant commun ities. it also exhibited smaller population peaks on some monocultures of s mooth cordgrass, Spartina alterniflora Loiseleur-Deslongchamps, during the winter months, but these increases were most likely the result of immigrati on. Adult leafhoppers migrate from mixed herbaceous plant communities durin g the winter months, when these plants experience a substantial dieback, to patches of S. alterniflora. Moreover, marked adult C,floridana showed a gr eater tendency to disperse from monocultures of S, alterniflora compared wi th mixed herbaceous communities during the spring. This is consistent with previous studies, which indicate that this leafhopper tends to feed and ovi posit on herbaceous plant species during the spring and summer months, a pe riod when these plants exhibit rigorous growth.