Co-existence of larval zygoptera (Odonata) common to the Norfolk Broads (U.K.) : I. Temporal and spatial separation.

The temporal and spatial components of resource partitioning were investigated in an assemblage of zygopterans. Spatial separation appeared to be relatively more important to their co-existence than temporal separation. Spatial differences separated Coenagrion pulchellum from the other species, Enallagma cyathigerum from both Ischnura elegans and Erythromma najas, and to a small extent I. elegans from E. najas. Difference in size (temporal separation) was important to the co-existence of I. elegans and E. najas (through a difference in final instar size), and may have been important in assisting the spatial separation of E. cyathigerum (through displacement of life cycles). This arrangement appears to differ from that of other aquatic insects for whom temporal separation through life cycle displacement is a very important component of community structure.