Ballistic defaecation by anisopteran larvae (Odonata): a way to increase foraging success?

The article considers the phenomenon of ballistic defaecation by odonate larvae, exhibited by certain Anisoptera but not by any Zygoptera, and explores two possibilities: (1) that ballistic defaecation in Anisoptera may correlate with increased foraging success (the ‘Wudkevich Hypothesis’) by distancing the prey’s alarm pheromone, persisting in the pellet after defaecation, from the larva’s ambush…

Reproductive behaviour of Odonata: the history of a mystery

The main, externally visible components of odonate reproductive behaviour were known from published accounts for about 300 years before sperm displacement during copulation was first described. The latter discovery, revealed by Jonathan Waage in 1979, revolutionised the interpretation of odonate reproductive behaviour, allowing it for the first time to be interpreted convincingly in the context…

A synopsis of the genus Triacanthagyna (Odonata: Aeshnidae)

This synopsis of adult Triacanthagyna includes the revalidation of two species thought to be synonyms (T. nympha and T. obscuripennis), the description of a new species (T. williamsoni; type locality: Peru, Tingo María), keys to both sexes, illustrations of diagnostic characters, and distribution maps of all species. A phylogenetic assessment of the nine species is…

Odonata from the Republic of Mongolia and from the Autonomous Region of Inner Mongolia

Thirty-five dragonfly species are reported from Mongolia and Inner Mongolia. Three are first records. A non-parametric test is used to determine the total number of species to be expected. It suggests that the current number of 62 may be asymptotically complete, except for some specific zones like the Bulgan valley in the south-west, and the…

Lamproneura lucerna gen. nov., sp. nov. from Venezuela, and Cyanallagma ferenigrum sp. nov., a remarkable new species from Brazil (Odonata: Protoneuridae, Coenagrionidae)

Lamproneura lucerna gen. nov., sp. nov. (Protoneuridae) is described from a male from the Turimiquire mountains, in northeastern Venezuela. Penis morphology places the new genus close to Forcepsioneura, Psaironeura and Roppaneura., The first Venezuelan record of the genus Phasmoneura is presented. Cyanallagma ferenigrum sp. nov. (Coenagrionidae) is described from a male and a female from…

Nested-subset structure of larval odonate assemblages in the Enoree River basin, USA

Communities have a nested-subset structure if the species found in species-poor assemblages are also found in progressively more species-rich assemblages. This nested-subset structure can be caused by differential colonization rates among species, differential extinction rates among species, or nested niche space. In this study, the assemblages of larval odonates in the Enoree River of South…

Population dynamics of Mortonagrion hirosei (Odonata: Coenagrionidae)

The mark-and-recapture method was used to study the population dynamics of the endangered brackish water species, Mortonagrion hirosei, in a small reed community of an estuary in the warm-temperate zone of Japan. The flying season was from late May to early August. The age structure showed that newly emerged adults always stayed in the reed…