Mating behaviour in Moina brachiata (Jurine, 1820) (Crustacea,Anomopoda)

Information on mating behaviour in Anomopoda isavailable for very few species only, though matelocation and recognition certainly play an importantrole in maintaining reproductive isolation betweenspecies. Ephippial females and males of Moinabrachiata were observed in a drop of water under amicroscope for 10–20 minutes. Different combinationsof specimens were used, but copulation was onlyobserved when two males and two ephippial females wereplaced together. Males were very active, and oftentried to grasp a female, whereas females usually madeattempts to escape during the entire period of mating.Three phases were recognized: capture, positioning andcopulation. The male captured the female from thedorsal side, then moved to the ventral side and tooka position with its length axis being perpendicular tothat of the female, forming a sort of cross.Thereafter the pair started rotating around the lengthaxis of the female, while the male pushed thepostabdomen into the females brood pouch. Copulationlasted from 16 to 25 seconds. When different kinds offemales were used, males showed preference forephippial females with an empty ephippium and enlargedovaries. Our results indicate that not only visual andtactile cues may be important in identifying speciesidentity and receptivity of the female, but alsochemical signals.