Abstract
The study was carried out in the Parambikulam Wildlife Sanctuary, in Kerala during 1994-1997 with an objective to prepare an inventory of insects belonging to Hymenoptera (limited to macro forms) and Lepidoptera in the different forest types and to estimate the insect diversity. Altogether 1049 species of insects belonging to 13 orders and 106 families were collected from the study area. The overall diversity index for the study area was significantly higher in the moist deciduous forest (4.835) than that in the teak plantations(4.318). The diversity index for evergreen based on ten months data was 4.509. The overall diversity index varied significantly between years in the study area. Species richness index for evergreen was the highest (6.82) suggesting the highest diversity in the evergreen. Speceis richness index for moist deciduous was 5.37 as against 4.5 teak plantations. Coleoptera was the most dominant group in the moist deciduous forest as well as in the teak plantation. In the evergreen,the most dominant group was Lepidoptera. The dominant butterfly families recorded in the Sanctuary are Nymphalidae, Pieridae, Lycaenidae, Satyridae and Papilionidae followed by Hesperidae and Danaidae. The dominant moth families are Noctuidae, Geometridae, Pyralidae and Arctidae which contained the maximum number of species. The dominant, macro hymenopteran families were Formicidae, Sphecidae, Pompilidae and Apidae which contained the maximum number of species