A Escolha críptica do macho e o polimorfismo cromático de fêmeas em Ischnura fluviatilis (Odanata: Coenagrionidae)

Abstract

In many animals. females show preference for males of variable quality with specific features. At the some time, males may also exert mate choice and show preference for determined female phenotypes. Male choice sometimes can be cryptic. when males do not actively choose among different females, but adjust investment in courtship or copulation according to female quality. As a consequence, sexual selection may result in variations within each species that may be restricted to sex, such as polymorphic females. In Ischnura damselflies, females usually exhibit two or more morphotypes. One female morph resembles male conspicuous blue coloration and behavior, while other morphs are usually cryptic. A great deal of studies has attempted to unravel the maintenance of female polymorphism in natural populations. Recent evidence suggests that different selective pressures, such as predation and longevity, act differently in each morph. Therefore. here we considered cryptic male choice as one of these factors, hypothesizing that males invest more time in copulation with one morph in detriment of the others. For this, mating pairs of I. fluviatilis were observed and the relationships between copulation duration and female body size and fecundity of different female morphs, and male body size were analyzed. Our results show that male size and female morph may predict the duration of copulation. These results add evidence to literature that different selective pressures act in female morphs of polymorphic damselflies.