The biochemistry of locusts. 2. Carotenoid distribution in solitary and gregarious phases of the African migratory locust ( Locusta migratoria migratorioides , R. & F.) and the desert locust ( Schistocerca gregaria , Forsk.)

The tremendous destruction which can be caused by regions of black pigmentation.At adult emergence locust plagues is widely appreciated, but, although there appears to be little black pigment and the locust research has attracted the interest of a large colour is greyish brown, but on reaching maturity number of workers, the biochemical aspects of the the males become bright yellow and the females problem have received little attention.dark brown.The overall colour pattern is very Uvarov (1921) was the first to appreciate the stable.The coloration of solitary Locusta, on the significance of the different forms of Locusta migraother hand, varies considerably; solitaries are toria, and his theory ofphases as applied to Acrididae generally lighter coloured than gregaria and tend to which swarm is now universally accepted.In the adopt the colour of their environment (Faure, 1932).solitaria phase locusts live in isolation; this implies They contain little, if any, black pigment and do not that they are independent of their neighbours rather undergo colour changes at maturity.than that they are particularly scarce.In the Solitary and gregarious Schistocerca exhibit very gregaria phase hoppers (nymphs) occur in dense much the same characteristics as do the correspond- bands, keep close to each other, and march together.ing Locusta, although the pigment pattern is differ- Gregarious adults form vast swarms which keep to-ent.The coloration of gregarious hoppers is very gether even in flight.The two extreme phases are stable and in the later stages the insects are lemon connected by a complex series of transitional forms yellow with very pronounced black patterns.which are descriptively named transiens.Factors Immature adults are generally pinkish with small