Author : Khin Nyunt Yee

Summary : The presence of mango leafhoppers stylopized by Halictophagus sp. on two cultivars was investigated. The density of Idioscopus clypealis was the highest among the three leafhopper species on mango. Aside from the reported I. clypealis, Halictophagus sp. also parasitized I. niveosparsus and Bakera nigrobilineata. The mean weekly parasitization rates reached 16.6% on I. clypealis, 16.6% on I. niveosparsus and 2.85% on B. nigrobilineata, based on extrusions. The lowest year-long parasitization rate was observed on B. nigrobilineata. The parasitization rate was not influenced by density of I. clypealis but positively influenced by temperature. The density of the hosts and environmental factors did not influence the parasitization rate on both I. niveosparsus and B. nigrobilineata. Hundreds of globular eggs hatched by batch inside an ovisac into C-Shape or shrimp-like triungulins. The free-living elongated sub-oval or tubular triungulins emerged singly from the female cephalothorax and infected leafhopper nymph hosts, then molted into apodous larval instars inside the new hosts. Super-parasitization occurred with maximum three parasitoids per host. Dark, hard C-shape and soft white larvae were found inside the parasitized hoppers. The anterior region of male pupa and of the adult female extruded through the intersegmental membrane of the abdomen of the host. The adult free-living adult male and the neotenic female showed extremely sexual dimorphism. Male extrusions affected the length of the whole body, abdomen, forewing, hindwing and the width of the hindwing of the adult male I. clypealis. The parasitization of Halictophagus sp. also reduced the size of the seminal vesicles in male I. clypealis.