Phenotypic plasticity represents an adaptive tool in organisms including odonates to cope with heterogeneous environmental conditions. However, while some odonate species can occupy various changing habitats, other species are adapted to a narrow range of environmental conditions. Commonly, behavioural modifications are applied to avoid detection and encounters with predators. But reduced behavioural activity results in…
The damselfly species Paracercion melanotum has been found to be the most abundant species in damselfly larval communities on Okinawa-zima Island in southwest Japan. To clarify differential susceptibility to predation, a possible factor affecting relative population densities in larval communities, between Paracercion melanotum and a less common damselfly species, Ischnura senegalensis, laboratory experiments were conducted…
Odonates have been recognized as an important group for evaluating ecosystems since they are used as bioindicators of the conservation status of the habitat they occupy, in addition to being generalist predators feeding on invertebrates and small vertebrates. In this work, the biodiversity of adult odonates from a locality near the San Marcos River, in…
Frogs are important predators of Odonata. We investigated frogs catching Odonata prey by means of slow-motion filming in the field in order to understand the prey–predator interactions. In particular, we aimed to analyse kinematics of captures, and of Odonata fleeing, through evaluation of frame-by-frame filming; 122 (20%) of 613 events were analysed. While dragonflies were…
From their earliest appearance in the fossil record, dragonflies have clearly taken a different approach to flight than other insect groups. Even the superficially similar Neuroptera do not fly like dragonflies. Flight specialisation has enabled dragonflies to occupy a range of niches, as specialised predators of flying insects, for around 300 My.
Predator escape behaviour is a critical component of dragonfly life history. Flight initiation distance is the distance at which escape commences, and is well studied in vertebrates, barely studied in invertebrates, and entirely unstudied in dragonflies. Here we test four principles regarding flight initiation distance as derived from studies of vertebrates to examine if they…
The estimation of lifetime egg production (LEP) is a central question in ecology, since the number of eggs produced determines the potential size of the following generation. In this study, I tried to obtain a rough estimation of the LEPs in libellulids in outdoor cages. The main questions were: (1) does hand feeding influence females’…
It has been shown that life history, behavioural as well as morphological traits vary with the habitats occupied by odonate larvae. Here we ask the following questions: (1) Are the morphological traits, which are associated with perception and foraging, related to the larval habitat? (2) Do these traits influence foraging success and growth rate? We…
A singular observation of an adult Tettigonia viridissima (Tettigoniidae) that captured a female Eutolmus rufibarbis (Asilidae) sucking a male Lestes sponsa (Lestidae) is reported. The reciprocal predation of Odonata, Asilidae, and Saltatoria (Ensifera, Caelifera) hitherto recorded in Europe is compiled and augmented by unpublished data on asilids as predators of odonates. Heavy predation by robber-flies…
Zygoptera show two perching modes, one with wings closed and one with wings open. These perching modes are distributed unequally through the suborder; most Zygoptera perch with closed wings, but species in 43 genera of eight families at least occasionally – in most cases usually – perch with open wings. Alternative hypotheses to explain this…