robber fly (Promachus yesonicus)
attempting two tasks at the same time, accomplishing neither; falling between two stools; (lit.) catching neither the horsefly nor the bee
horsefly and bee; horsefly and wasp
deerfly (Chrysops suavis)
Tabanus trigonus (species of horsefly)
robber fly (any fly of family Asilidae)
Tabanus chrysurus (species of horsefly)
bee fly (any insect of family Bombyliidae)
soldier fly (any fly of family Stratiomyidae, esp. species Stratiomys japonica)
hoverfly (Syrphidae spp.); syrphid; drone fly (Eristalis tenax)