Bean seed fly

Bean fly at three life stages. Image: Onions Australia

  • Bean fly affects onions, leeks, garlic, Brassicaceae species, tomatoes, potatoes and corn.
  • The adults are long and thin with grey bodies.They are about 6mm in length, with black legs and clear wings. Their eyes are large and reddish purple.
  • The eggs are enclosed within a hardened, darkened larval skin, that are oval, red-brown and 8mm long.
  • Larvae are creamy yellow to white 8mm long when fully grown. The body tapers toward the head end but lacks a distinct head and legs.
  • Damages bulbs, seedlings.
  • Look for a borer in the lower leaf and the larvae can
  • make corridor-like excursions into the upper leaf. T the mines may be distinguished from other similar flies because the mines of bean fly harbour several larvae.
  • Spread by infested soil and plant material.

High priority pest of: Onions, Vegetables

Scientific name: Delia florilega
EPPRD Category:
Life Form: Flies & Midges (DIPTERA)

Pest Documents

FS: fact sheet

CP: contingency plan

DP: diagnostic protocol