A review of the reproductive behavior of Polyphemus pediculus (L.) Müller (Crustacea: Branchiopoda)

Abstract

The reproductive behavior of Polyphemus pediculus (L.) includes mating, laying of resting eggs and giving birth to juveniles. All these forms of behavior are performed in a population daily and simultaneously by means of individual and social actions. Individual behavior is manifested by certain sets of stereotyped movements which can be observed at any time of the day and at any location in a water body. Individual behavior has an episodic, stable character and low intensity. Social behavior is accomplished by specimens of similar physiological state who form transitory swarms. They form within the main continually existing main swarms of the population. Social behavior is rhythmic and of high intensity. Reproductive parthenogenetic swarms first form around dawn and later during the day: about noon in May–July and before sunset in Autumn. As swarms of parthenogenetic females disintegrate, swarms of old gamogenetic females form and mass laying of resting eggs begins. Young gamogenetic females and males swarm only when resting-egg-laying swarms disintegrate. Parthenogenetic reproduction peaks in northern Russia in May and August and persists until late September. Swarms of resting-egg-laying females form once a day around dawn, from May to September. Mating swarms form in summer in midmorning, at twilight and on moonlit nights. In Autumn, there is only one peak of mating, in midmorning. Intensity, duration and time of manifestation of different forms of social behavior change from spring to autumn. Location and character of their manifestation are predictable.