Seed maggot (Delia platura) are the larvae of the bean root maggot fly. The size range is 1 – 7 mm, and on maturity, the larvae pupate in the soil. The adult fly emerges from the puparium and burrows to the soil surface. The fly is about the size and appearance of a bush fly, but more slender and hairy, with greyer wings. Eggs are laid in the soil, and on hatching the larvae burrow to the germinating seed or emerging shoot, and begin to feed. Lupin, pea or bean seedlings with one or two true leaves begin to wilt and die, while unaffected seedlings are vigorous and growing well. When dug from the soil, the root and stem are dark grey and soft, with white or cream maggots inside. In some cases the cotyledons are discoloured and mushy, with small maggots burrowing through them.