Oviposition and refractory periods of the small water strider Microvelia horvathi (Heteroptera: Veliidae) after a single mating event

Multiple mating can be costly, but also beneficial for females. When the costs outweigh the benefits, mated females can be reluctant to remate for some time. Conversely, females will be likely to remate when they need to replenish sperm and/or receive nutrients contained in the accessory ejaculate substances. Water striders have been commonly used in mating studies as many show a vigorous struggle between the sexes. Generally, water strider females frequently mate with many males and lay many eggs during mating period. However, little is known about their oviposition and refractory periods after an initial mating event. In this study, we revealed that single-mated females of the small water strider, Microvelia horvathi, could lay eggs for 40 days, reflecting approximately half of their potential oviposition periods. It suggested that M. horvathi females do not need to mate to replenish sperm for some time once they mate. Our results also showed that no female remated after 1 or 3 days of an initial mating event. The proportion of female remating increased with time after the initial mating, however, remating levels reached 26.7% even after 14 days. In this sense, any significant cost of mating outweighs the benefit, which might be one of the factors lowering their remating levels.