A preliminary study on female-limited colour polymorphism in Lestes sponsa

Female-limited colour polymorphisms are widespread in Odonata, usually showing an androchrome and one or more gynochromes. Androchromes have been hypothesized to function as male mimics with a consequent decrease of male harassment, although males may also learn to recognize the different female colour morphs. In the Eurasian damselfly Lestes sponsa, the occurrence of two female…

Geographical variation in egg diapause in Sympetrum frequens

The effects of photoperiod and temperature on the termination of egg diapause were examined in Sympetrum frequens. Eggs were obtained from adult females collected from three locations in Japan and incubated under short- or long-day photoperiods at a constant temperature of 25, 20, or 15°C. Egg diapause was eventually terminated in all treatments. Because differences…

Odonata of Itatira, a Brazilian semi-arid area in the state of Ceará

The present study provides the first odonate survey for the Brazilian Caatinga, including species habitat information. Specimens were collected during five days in both dry and rainy seasons of 2011 in the municipality of Itatira, state of Ceará, located in the semi-arid region of northeastern Brazil. Adult individuals of 37 species were documented, the highest…

Phoenicagrion trilobum, a new species of damselfly from Peru (Odonata: Coenagrionidae)

Three species of Phoenicagrion are known from the north-eastern Amazonian part of Peru: P. flammeum, P. paulsoni, and a third undescribed species. In 2009 and 2010 several specimens of this third species were collected in Loreto, making it possible to describe this species, here named Phoenicagrion trilobum (holotype ♂: Peru, Loreto department, Tahuayo River, 18 km E…

Reproductive behaviour and the system of signalling in Neurobasis chinensis (Odonata, Calopterygidae) – a kinematic analysis

The reproductive behaviour of the damselfly Neurobasis chinensis (Calopterygidae) was filmed at 300 and 600 frames per second in Thailand in spring 2009. This was subsequently viewed in slow motion for detailed analysis. Altogether we observed 26 matings at two different sites. Besides visual observations of behaviour of male–female encounters at the reproductive sites, we…

Winter survival by dragonfly adults in the Cape Floristic Region

Little is known about the ability of adult dragonfly individuals to survive into or over the winter in the Cape Floristic Region (CFR), a significant biodiversity hotspot in South Africa. Dragonfly species richness and abundance were recorded throughout winter and into spring in Jonkershoek Nature Reserve. Several environmental variables were also measured. Individuals of eight…

Are community patterns in flight height driven by antagonistic interactions?

Large libellulid dragonflies often fly higher than smaller libellulids. We hypothesized that this size-related pattern in flight height might be caused by aggressive displacement. We tested this hypothesis by using a 30 m “dragonfly zip-line” to reel dead dragonfly decoys of four species of different sizes (Erythemis simplicicollis, Libellula incesta, Pachydiplax longipennis, and Perithemis tenera) along…