Aquatic macrophytes are important substrates for Libellulidae (Odonata) larvae and adults

Abstract

Understanding the role of abiotic and biotic factors on biological communities is a challenge for ecologists. Individuals of the order Odonata have a close connection with these factors, which can influence the establishment of each stages of live. This study evaluated the relationship between habitat complexity and limnological variables on the diversity of Libellulidae larvae and adults. Our hypotheses were that (i) limnological variables would have a greater influence than habitat complexity on larvae and (ii) habitat complexity would influence more adults. Forty-six sampling sites were evaluated in the Brazilian Amazon region. Our results indicated the effects of limnological variables and habitat complexity on both life stages, with higher influence of the first on larvae and the second on adults, mainly for species composition. The abundance of the Eichhornia azurea, which has enormous morphological plasticity, together with the presence of a range of other macrophyte species provides different habitat architectures, with more suitable microhabitats for different odonates. The habitat complexity metrics had combined effects on the larvae, presumably because of the greater availability of refuges from predators and food sources. In contrast, in the adults, the relationship with habitat complexity is associated with the availability of ovipositing sites and perches.