none Experiment where variable densities (1, 2, 5, 10, 25, 50, 100 and 150) of the parasitoid (5-7 d postparasitised aphids (Aphis craccivora Koch) -- parasitised by aphidiid parasitoid Trioxys indicus Subba Rao & Sharma) were exposed to individual hyperparasitoid Alloxysta pleuralis (Cameron) indicated the following: with increase of initial host (primary parasitoid) densities the number of hosts hyperparasitised increases sigmoidally reaching to a plateau at 50 host similar to the type 3 functional response of Holling; the curve was described by a logistic equation; greater host mortality was recorded at lower initial host densities ( less than or equal to 50). Parasites diseases and disorders; Parasites; Insect parasites; Hosts; Insect hosts; Ecology; Population dynamics; Population structure Trioxys indicus (Braconidae); Hymenopteran parasites; Alloxysta pleuralis; Hyperparasitic on hemipteran host; Population density effects on parasite prevalence & sex ratio; Hemipteran hosts; Aphis craccivora, hymenopteran hyperparasite biology relations; Population density; Hymenopteran parasite prevalence & sex ratio relationships Alloxysta pleuralis (Cynipidae); Hymenopteran hosts; Trioxys indicus; Hyperparasite on Hemiptera, host density effects on prevalence & sex ratio; Hyperparasitism; Of Trioxys indicus in Aphis craccivora (Hemiptera); Host density effects on prevalence & population sex ratio; Population sex ratio; Hymenopteran host population density relationships Aphis craccivora (Aphidoidea); Hymenopteran parasites; Alloxysta pleuralis in Trioxys indicus; Hyperparasitism; By Alloxysta pleuralis in Trioxys indicus (Hymenoptera); Hyperparasite biology