MATE SELECTION AND MATING-BEHAVIOR IN SPIDER CRABS

Female spider crabs can only mate after the terminal moult, which mean s that they must either mate whilst soft-shelled after moulting, or su bsequently when hard-shelled. There is evidence that some, at least, d o both, whereas the majority of crabs mate in only one or other of the se states. The mating behaviour, and the means of detecting receptive females, have been studied in a spider crab, Inachus dorsettensis. In this species, mating is predominantly hard-shelled, and receptive fema les are recognized by their emission of chemical pheromones. The impli cations of the behaviour patterns for male mating efficiency, sperm co mpetition and female reproductive success are discussed. Mate selectio n and mating behaviour in other spider crabs are compared with I. dors ettensis. Reasons for similarities and differences are reviewed. (C) 1 997 Academic Press Limited.