ECDYSTEROIDS IN ADULT FEMALES OF A WALKING WORM - EUPERIPATOIDES LEUCKARTII (ONYCHOPHARA, PERIPATOPSIDAE)

Onychophorans possess a combination of annelidan and arthropodan chara cters and are always prominent in discussions of arthropod evolution. The chitinous cuticle is moulted periodically in juveniles as well as in adults. Using radioimmunoassay (RIA) and high performance liquid ch romatography (HPLC), the presence of free and conjugated ecdysteroids is reported in the body wall, digestive tract, slime gland and ovary/u terus of adult females of Euperipatoides leuckartii. Within free ecdys teroids, ecdysone is dominant. The functional significance of ecdyster oids is discussed in the light of the evolutionary history of moulting hormones.