An emergence study of Petalura gigantea (Odonata: Petaluridae)

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

Larval habitat and behaviour of Phenes raptor (Odonata: Petaluridae): a review of current knowledge, with new observations

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 This paper provides a review of previously published and unpublished information, and new observations on…

Reproductive behavior of Acanthagrion truncatum Selys, 1876 (Odonata: Coenagrionidae)

Behavioral data on Neotropical coenagrionids is still scanty, with very few studies on their reproductive behavior. Here we present the first description of the reproductive behavior of A. truncatum in a high density population in the Brazilian Neotropical savanna. The observations were made at a pond in an ecological reserve. Males remain at the water…

Aerial dispersal of freshwater gastropods by dragonflies (Odonata)

At a ditch near Tribsees in northeastern Germany a young individual of the freshwater snail Lymnaea stagnalis was photographed while attached to the dorsum of the abdomen of a female Aeshna viridis, after the odonate took off after oviposition in Stratiotes aloides. This is the first known case for odonate-born dispersal of freshwater gastropods.

Sexual size dimorphism, mating system and seasonality of a Neotropical damselfly, Telebasis carmesina (Coenagrionidae)

Our understanding of mating systems is highly skewed toward temperate examples. This study investigated the mating system, sexual size dimorphism and seasonal variation in local distribution and abundance of male and female Telebasis carmesina, a common damselfly in Brazilian tropical savanna. In a natural reserve, daily census and behavioral observations were made throughout 1 year…

Clutch size and egg production in Orthetrum nitidinerve Selys, 1841 (Anisoptera: Libellulidae): effect of body size and age

Clutch size is an important fitness component often quantified artificially by inducing oviposition in libellulid females. Female behavior and egg production of the yellow-veined skimmer, Orthetrum nitidinerve, were studied in northeast Algeria during its reproductive season. Data on reproductive behavior and biology of this Mediterranean endemic species has not been published previously. Males guarded territories…

Morphology of exophytic ovipositors in dragonflies (Odonata: Gomphidae, Corduliidae, Libellulidae), with particular reference to ovipositor muscles and sensilla

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,…

Morphology of female external genitalia in Phenes raptor (Odonata: Petaluridae)

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…

Ovipositor morphology and egg laying behaviour in the dragonfly Lestes macrostigma (Zygoptera: Lestidae)

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…