Black soldier fly (Hermetia illucens (Linnaeus, 1758)) larvae inhibit oviposition of house fly (Musca domestica Linnaeus, 1758) by releasing a semiochemical, although in some situations, inhibition is only partial. We hypothesized that there is a certain period in the life cycle of black soldier fly when it can cause antibiosis of the house fly. Choice and non-choice tests were used to separately examine the effectiveness of each developmental stage of black soldier fly (egg, larval (phase I, II, and III), prepupal and pupal stages) and crude extract of larvae on house fly oviposition. Tests using each developmental stage were compared with controls lacking black soldier fly. The effects of black soldier fly on the number of newly hatched house fly larvae were evaluated and there was a significant difference between the test and control in the number of eggs laid by house fly for all phases of the black soldier fly larval stage. Strong inhibition was found in some black soldier fly larval phases. Significant differences in the numbers of house fly eggs oviposited in food containers treated with crude extract were found when compared with a control, confirming that chemicals from black soldier fly larvae resulted in inhibition of oviposition of house fly. The results from experiment also indicated that chemicals from black soldier larvae influenced the number of house fly larvae newly hatched from eggs.

Simulium triglobus Takaoka & Kuvangkadilok from Thailand, in the Simulium (Simulium) multistriatum species-group, is unique among species in the family Simuliidae in having the female terminalia with three spermathecae (rather than one spermatheca). This species was described from Nan province, northern Thailand based on larvae, pupae and females but its male has remained unknown. In this study, the male of S. triglobus is described for the first time based on adult males reared from pupae collected from the type locality. The most distinctive characteristic of the male of S. triglobus is the shape of the ventral plate, which is hexagonal when viewed ventrally. No other members of S. multistriatum species group known thus far have such a unique ventral plate. In addition, the number of upper-eye (large) facets and color patterns of the legs can be used to differentiate this species in the male from other members of the S. multistriatum species-group. Mitochondrial cytochrome c oxidase I sequences enabled association of adult male specimens of S. triglobus with previously known life stages. Phylogenetic analysis based on these sequences revealed that specimens of S. triglobus formed a strongly supported monophyletic clade, being genetically distinct from other members of S. multistriatum species-group in Thailand.