Studies of Some Species of Cicadellidae (Homoptera) of Economic Imprtance in the Sudan.

Abstract

The thesis embodies the results of studies on the Cicadellidae of the Northern Sudan. Special attention was paid to the taxonomy of the various species. During the survey 20 species of Cicadellidae were found associated with various host plants including cotton. The different species have been fully described, based mainly on the genital structure of the male. A key to the separation of the species has also been presented. Besides this, host plants which include many new records have been listed for most of the important species. Of the 20 species, two were described as new to science, namely Empoasca abdini sp.n. and Balculutha venkatrami sp.n., 15 are new records. The later species was found on cotton plants in its early stages of growth. The discovery of this species is considered significant from the point of view of the present jassid control methods. The taxonomic studies revealed some interesting features in the morphology of the group, recorded for the first time. In Paradorydium sp. the subgenital plates are absent, and in Erythroneura lubia China, the exact nomenclature and the function of the abdominal apodeme were reported for the first time. In Cicadella sp., where the submarginal vein extended around apex to apex of only R instead of R M. Future outlines of work on this neglected branch of entomology have been suggested.