Slow-motion analysis of female refusal behaviour in dragonflies

By means of slow-motion film analysis we found new female refusal behaviour patterns against male harassment in a variety of Odonata species. Often, females could escape simply by flying faster than males. Due to the morphological preconditions, there were differences in the two suborders. In Anisoptera, several behavioural specialities were analysed: (a) females of Aeshna…

A preliminary study on female-limited colour polymorphism in Lestes sponsa

Female-limited colour polymorphisms are widespread in Odonata, usually showing an androchrome and one or more gynochromes. Androchromes have been hypothesized to function as male mimics with a consequent decrease of male harassment, although males may also learn to recognize the different female colour morphs. In the Eurasian damselfly Lestes sponsa, the occurrence of two female…

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…

The female of Leptobasis melinogaster González-Soriano (Odonata: Coenagrionidae)

The female of Leptobasis melinogaster González-Soriano, 2002 is formally described and illustrated. Female L. melinogaster can be distinguished from the seven other known congeners by the shape and presence of a ventral lobe below the rounded lateral margins of the posterior and median lobes of the prothorax as well as by the dark apices on…

Rediscovery of Mesagrion leucorrhinum (Zygoptera: Megapodagrionidae): a “formal” description of female and ultimate stadium of larva with notes on habits

Adult female and ultimate stadium larva of Mesagrion leucorrhinum are formally described and illustrated based on material from three locations in Antioquia, Meta and Cundinamarca Departments, Colombia. The species is sexually dimorphic. The ♀ is distinguishable from other related genera by a pair of notches in the prothoracic anterior lobe and shares with Heteropodagrion and…

Effects of male harassment on females’ oviposition behaviour in Libellulidae (Odonata)

I investigated whether the level of male harassment affects females’ oviposition behaviour, such that females oviposit unguarded under suboptimal conditions and/or vary oviposition duration, dip number, dip frequency or number of oviposition site changes. The study species were the libellulids Crocothemis erythraea, Ortbetrum chrysostigma, Pantala flavescens, Sympetrum fonscolombii, Trithemis annulata and T. kirbyi ardens. Only…