Odonata flight performance capabilities and behaviour and their body and wing form diversity are explored, and their interrelationships discussed theoretically and from observational evidence. Overall size and particularly wing loading appear predictably to be related to speed range. In Anisoptera at least, relatively short bodies and long wings should favour high speed manoeuvrability, though further…
Most species of petalurid dragonflies have a fossorial larval stage, which is unique in the Odonata. Larvae typically excavate burrows in soft peaty soils in mires, seepages or along stream margins, which are occupied by a single larva throughout the long larval stage. This paper reports on a study of burrow morphology in Petalura gigantea,…
In libellulids, mature oocyte size varies within and between individual ovaries. The regulating mechanism is not yet understood. Variations in the contents of the follicle cells, and thereby their ability to secrete material into the oocyte, might explain some of the observed differences in oocyte size. We therefore investigated the follicle cell surface, the interstitial…
A comparative study of female external genitalia was carried out in representatives of three dragonfly families that lay eggs exophytically, with special emphasis placed on skeletal musculature and sensilla. Female external genitalia are characteristically represented by the vulvar lamina and rudiments on the 9th sternum. In a gomphid, Gomphus vulgatissimus, and a corduliid, Cordulia aenea,…
The exoskeleton of the female genitalic region in Phenes raptor is described based on light microscopy and scanning electron microscopy. It is shown that in this species the pattern of sclerites, articulations, processes, and apodemes is overall the same as in other ovipositor-bearing Odonata, i.e. Zygoptera, the anisozygopteran Epiophlebia, and the anisopteran Aeshnidae. However, many…
Lestes macrostigma is a stenotopic dragonfly species of Western Palaearctic distribution that has high conservation status almost throughout its range. It inhabits mainly brackish water with a typical plant species, sea club-rush Bolboschoenus maritimus. Due to the absence of special investigations, the nature of this insect–plant association is not clearly understood, but it was supposed…
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…
Ten common libellulid species perch along the shoreline of lakes and ponds in South Carolina, USA. We collected individuals at five ponds throughout summer 2005, weighed them in the field, and calculated wing loading (N·m2) and wing aspect ratios from digital photographs. We measured the perch-height preferences of these species in ‘low perch’ (10, 20,…
The final instar of Bayadera strigata Davies & Yang, 1996, from Yunnan Province, China, is described and illustrated for the first time. This study confirms several characters as
being typical of, or unique to, the genus Bayadera and discusses them in comparison to other genera.
Cyanallagma demoiselle sp. nov. (holotype male deposited in DZUP: Brazil, São Paulo State, Cananéia, Ilha do Cardoso State Park), a new small greenish blue and black damselfly, is described, illustrated, and diagnosed based on males and females from the southeastern Atlantic Forest.