Two distinct emergence styles have been reported in odonates, with both the upright and hanging back emergence reported in the Petaluridae, between and within individual species, including Petalura gigantea. This paper reports three additional observations of upright emergence in P. gigantea, providing further evidence that this emergence style is the norm for the species.
As warm-adapted insects of tropical origin, Odonata cope with cold periods by seasonal regulation and diapause. A model for larval-overwintering species is proposed with three response patterns related to the timing of emergence, which can be predicted from seasonal cues during the last few stadia. For emergence during the present season, there is an often time constrained pre-emergence development, accelerated by long days and higher temperatures.
Emergence studies in Odonata provide information on the behaviour, ecology and fundamental demographic parameters in population studies. This paper reports on a study of sex ratio at emergence, pattern and duration of the emergence season, and potential cohort splitting in Petalura gigantea. Sex ratio at emergence varied among years, habitat patches and swamp types. Across
Phenes raptor is one of only two petalurid dragonflies with a documented non-fossorial larval lifestyle. There have been few reported observations of larvae and their habitat, and the behaviour and ecology of this unique South American species remain largely unknown. This paper provides a review of previously published and unpublished information, and new observations on…
The behaviour of Anisoptera during the period between emergence and the onset of sexual activity is poorly known, mainly because freshly emerged adults are hard to follow. In the present study the system RECCO® Transmitter/Receiver and custombuilt tags made from Schottky diodes and copper wire were used to monitor freshly emerged Anisoptera. The system had…
Microneura caligata (Hagen in Selys, 1886) is an endangered damselfly presently known from five localities in the central mountains of Cuba. The precise systematic position of this species within the former Neotropical Protoneuridae has been the subject of debate, with previous results from a phylogenetic analysis based on morphology suggesting that the genus Microneura should…
Coenagrion mercuriale is a threatened damselfly in most parts of its geographic distribution. It is listed as endangered in North Africa, where no data on its biology or ecology are available. This study aims to illustrate the reproductive behaviour and habitat preferences of adults in a population located in north-east Algeria, representing the southern limit…
A written description and illustrations of the final stadium larva of Nesciothemis farinosa are presented, based on larvae and exuviae collected in Namibia. The larvae were reared in the laboratory until emergence. Additionally, information on larval microhabitat, behaviour and development is provided.