A natural flightless mutation in the ladybird, Harmonia axyridis

A homozygous flightless strain, obtained by selection from a laboratory pop ulation of Harmonia axyridis Pallas (Coleoptera, Coccinellidae), has been r eared under controlled conditions since 1982 after sampling in China. The a dults of this flightless strain have normal elytra and wings but drop almos t vertically when they attempt to fly. The origin of this mutation, whether laboratory or natural, is discussed. As the mutation does not affect the f itness of the beetles, this flightless strain can be used in biological con trol. Releasing flightless adults rather than larvae should provide the pot ential for more continuous control of aphids by both larvae and adults.