SPATIAL PATTERNS OF THE PARASITIC MITE HEMISARCOPTES COCCOPHAGUS (ASTIGMATA, HEMISARCOPTIDAE) - HOST EFFECT, DENSITY-DEPENDENCE OF AGGREGATION, AND IMPLICATIONS FOR BIOLOGICAL-CONTROL

The spatial distribution of the parasitic mite Hemisarcoptes coccophag us Meyer on two armoured scale insects (Homoptera: Diaspididae) was hi ghly aggregated in the field. Mites were more aggregated on young than on ovipositing host scale females. No differences in the mite's distr ibution pattern were found between latania scale (Hemiberlesia latania e (Signoret)) and oleander scale (Aspidiotus nerii (Bouche)). Mite agg regation was density-dependent on ovipositing host females (the degree of overdispersion decreased as mite abundance increased), but density -independent on young females. The effect of density-dependent and ind ependent mite aggregation on the proportion of hosts escaping attack a t different parasite abundances was simulated, and its relevance to bi ological control of Diaspididae is discussed.