MORPHOLOGICAL VARIATION IN ADULT FEMALE COCCUS HESPERIDUM L. (HEMIPTERA: COCCOIDEA: COCCIDAE) IN POLAND

Abstract

MORPHOLOGICAL VARIATION IN ADULT FEMALE COCCUS HESPERIDUM L. (HEMIPTERA: COCCOIDEA: COCCIDAE) IN POLAND

This paper compares the variation of ten morphological characters of adult female C. hesperidum L. collected off (i) five different host plants and (ii) the stems, petioles and both leaf surfaces of Citrus, all from glasshouses in Poland. Four measured and six meristic characters were selected for biometric study. The mean and range of each of these characters varied between host plant species and with their position on Citrus. The main characters which varied between host species were the size and shape of the dorsal setae and the distribution and frequency of dorsal and ventral tubular ducts. Specimens off different parts of Citrus varied mainly in the frequency of the dorsal tubular ducts and the spiracular disc-pores. Pocket-like sclerotisations were noted for the first time in C. hesperidum; when present, they were in the stigmatic areas, close to a dorsal tubercle.

Key words: brown soft scale, Citrus limon, Ficus benjamina, Hedera helix, Iresine herbstii, Schefflera actinophylla, dorsal tubercles, host-induced differences.