Dragonflies from Rio de Janeiro State, Brazil: habitats and habits of the larvae

Abstract

Rio de Janeiro State is located in southeastern Brazil, occupying only 0,52% (44,268 Km²) of the total area  of the country. Species of 77 genera and 12 families are currently known to occur in this Stute: Calopterygidae (2 gen.): Dicteriadidae (1 gen.); Lestidae (1 gen.); Megapodagrionidae (2 gen.); Pcrilestidae (1 gen.): Coenagrionidae (14 gen.); Protoneuridae (5 gcn.); Pseudostigmatidae (1 gen.); Aeshnidae (10 gen.); Gomphidae (11 gen.): Corduliidae (2 gen.); Libellulidae (27 gen.). Informations about habitat preferences and habits (mode of existence) of larvae of 133 species of 62 genera were considered in this study, being 19 of them registered for the first time. lt was observed that species of 27 genera are lotic dwellers and those of 27 others associated with lentic habitats, Species of  8 genera occur both in lernic and lotic waters. There are no informations about larvae of 15 genera yet. In relation to the habits of the larvae it was observed that the majority of Zygoptcra from lentic habitats behave as climbers (e.g. Acanthagrion spp.. ldioneura ancilla, Ischnura spp., Lcptagrion spp., Telebasis spp.), as the major part of Aeshnidae too (e.g, Aeshna spp., Coryphaeschna spp., Gynacanthu spp., Neuraeschna costalis, Remartinia luteipennis). Representatives of these two groups become clingers in lotic habitats (e.g, Argia spp., Hetaerinu spp., Heteragrion spp., Limnetron spp ., Oxyagrion spp., Staurophlebia reticulata). Some Zygoptera has been classified secondarily as swimmers (e.g. Lestes spp., Perilestes fragilis), Alrnost all of the species of Gomphidae behave as burrowers. From the other side, the Libellulidae and Corduliidae has been considered as sprawlers in almost their totality.