Promachus yesonicus, or shioya-abu (塩屋虻, シオヤアブ) in Japanese, is a species of robber flies. In Japanese, "shioya" means a salt merchant (someone who makes or deals in salt), and "abu" means a horse-fly. This insect is called "shioya-abu" because the males have a white tip to their tail that resembles salt.
Promachus yesonicus is found throughout Japan from Hokkaido to Okinawa. They are visible from June to September.
Male Promachus yesonicus have a white cotton-like bud at the end of their tails, while females do not. Adults can reach 23–30 millimetres (0.9–1.2 in) in length.[1]
Female Promachus yesonicus in Tokyo
Male in Tokyo, Japan
Media related to Promachus yesonicus at Wikimedia Commons
Promachus yesonicus, or shioya-abu (塩屋虻, シオヤアブ) in Japanese, is a species of robber flies. In Japanese, "shioya" means a salt merchant (someone who makes or deals in salt), and "abu" means a horse-fly. This insect is called "shioya-abu" because the males have a white tip to their tail that resembles salt.