The large, endothermic dragonfly Anax junius regulates the temperatures of its thorax (Tth) and head (Th) during flight. At high ambient temperature (Ta) it is able to dispose of excess heat from the thorax by increasing hemolymph circulation to the abdomen, but recent evidence suggests that heat loss to the abdomen is largely passive at Ta<30 &deg;C. Nevertheless, these insects continue to reg...

Perfluorooctane sulfonic acid (PFOS) is a persistent and ubiquitous environmental contaminant that has been detected in organisms worldwide. Here, we evaluate whether long-term (1 and 4 months) exposure to PFOS contamination affects the behavioural performance of freshwater larvae of the damselfly Enallagma cyathigerum (Insecta: Odonata). Our results show reduced behavioural performance with in...

The final stadium larva of Coeliccia mingxiensis Xu is described and illustrated. The female adult is also described for the first time. The larva can be easily separated from all known Coeliccia larvae by the following distinct morphological characters: (1) prementum longest in all known Coeliccia larvae; median lobe with 4 pairs of premental setae and palpal lobe with 6 palpal setae; (2) caud...

Using bioclimatic belts as habitat and distribution predictors, the present study examines the implications of the potential distributions of the three Iberian damselflies, Calopteryx Leach (Odonata: Calopterygidae), with the aim of investigating the possible consequences in specific interactions among the species from a sexual selection perspective and of discussing biogeographical patterns. T...

Carajathemis simone n. gen., n.sp. from the state of Pará, Brazil, is described and illustrated based on 22 specimens collected in a "canga" (laterite) lake within the forest at the Flona de Carajás, Parauapebas Municipality. The new libellulid genus fits in the subfamily Sympetrinae and the male keys out to Erythemis in Garrison et al. (2006). The new taxon has a combination of characters that...

In the dragonßy Perithemis tenera Say, males defend territories around oviposition sites and defense of a site is critical for reproductive success. This study Þrst demonstrated that individual males variedconsistently inhow long theydefendedaparticular territorywithin aday(their “tenure”) and in the quality of the sites they defended. I then investigated a number of factors that may have affec...

I examined the effects of isolation on the structure of both adult and larval dragonfly (Odonata: Anisoptera) communities forming at physically identical artificial ponds over two years. Isolation, whether measured by distance to the nearest source habitat or by connectivity to multiple sources, was significantly negatively related to the species richness of dragonflies observed at and collecte...

1. In Great Britain the distribution of the riverine damselfly Calopteryx splendens is predominantly southern. However, the last decade has seen records of the species in previously unoccupied areas in the northeast of England, prompting speculation regarding northward range expansion. The current study is the first to quantify the physical features of the habitat that influence the presence of...

The larvae of seven species of Chlorogomphidae from South China are described based on reared larvae, i.e. Chlorogomphus kitawakii Karube, C. nasutus nasutus Needham, C. papilio Ris, C. shanicus Wilson, C. usudai Ishida, C. yokoii Karube and Chloropetalia soarer Wilson. The adult female of C. kitawakii is first described. Biological information on Chlorogomphidae is provided and a diagnosis of ...

The genus Mesamphiagrion Kennedy, 1920, occurs in the Pantepui region and northern Andes in South America and is most speciose in Colombia where the genus is less known. In this work, we record 10 species of Mesamphiagrion from Colombia, including four new species (Mesamphiagrion gaudiimontanum Bota-Sierra sp. nov., M nataliae Bota-Sierra sp. nov., M. rosseri Bota-Sierra sp. nov., and M. santai...