Robber Fly – Machimus Species

Robber Fly – Machimus species

color photo Robber Fly Machimus species


Family Asilidae – Robber Flies
Live adult robber flies photographed in the wild at various North American locations. Size: 15mm

color photo Robber Fly Machimus species mated pair

Male on left

Compared to dragonflies who are fast and agile, robber flies are often slow and clumsy, and miss more often than not. As far as I know, the huge Promachus does not even attempt mid-air captures. I’ve only ever seen them pounce on their prey who are busy feeding at flowers.

color photo female Robber Fly Machimus species


Range: North America east of the Rocky Mountains
Food: Adults suck body juices from small flying insects, larvae prey on insect larvae, especially beetles.
color photo Robber Fly Machimus species with damselfly preyRobber flies are fun to watch.  I watched this specimen hunt for perhaps 20 minutes – he made numerous attempts to catch various insects in mid-air, including one moth which eluded him three different times.

Reference:, Robbers in copulo – Machimus

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