A male Libellula depressa was observed to mistake a dark-green passenger coach for a water body thus establishing his territory over the surface of the vehicle and using the radio antenna as perch. A videopolarimetric analysis of the car body showed that the light reflected from the bonnet was highly and horizontally polarized with rather…
Gomphomacromia mexicana is shown to be a junior synonym of G. chilensis based on a comparison of the holotype male with the original description of G. chilensis and specimens identified as that species from Chile. Examination of a large series of specimens from central and southern Chile and Argentina identified both as G. paradoxa and…
The status of the Odonata as a model taxon for studying the evolution and diversity of reproductive behaviours is shown here to have declined relative to crickets and Drosophila. Very few available data on ejaculate size, the number of sperm stored by females and the duration of sperm storage reveal poor knowledge of these areas…
Information on larval biology of Macromia splendens was compiled and supplemented by hitherto unpublished data. Larvae inhabit mainly calm river stretches, sometimes artificial impoundments, and lentic margins of lotic sections. From the majority of records it is concluded that the larvae mainly dwell in sandy substrates in shallow water, which sometimes contains little leaf litter.
The taxonomy of the Gynacantha and Heliaeschna species from continental Africa is problematic, and available keys are unsatisfactory. ‘Traditional’ characters such as venation and ‘innovative’ ones like abdominal denticulation are evaluated and their variability is measured and discussed. G. quadrina is a synonym of G. africana and not of G. vesiculata, G. ochraceipes is regarded…
Co-occurring odonate species often perch at different heights. We studied the effects of interspecific and intraspecific interactions on perch-height selection by Perithemis tenera, Pachydiplax longipennis, and Enallagma spp. by creating artificial perch stations and comparing perch selection when species perched alone or together. We also compared the frequency of perch-height use in the presence or…
Zygoptera show two perching modes, one with wings closed and one with wings open. These perching modes are distributed unequally through the suborder; most Zygoptera perch with closed wings, but species in 43 genera of eight families at least occasionally – in most cases usually – perch with open wings. Alternative hypotheses to explain this…
Territorial behaviour associated with adult odonate feeding in a Bornean rain forest under-storey is described and its underlying causes are analysed. Immature males and females of all ages of Libellago hyalina defended perches along a narrow trail in kerangas forest, concentrating especially around patches of sunlight. Throughout the day there was displacement of individuals as…
In odonates, female specific color polymorphisms appear to be an evolutionary response to sexual harassment, but we know little about the decision rules males use when searching for variable females. For two sympatric species of Enallagma, we measured male responses to live female variants under field conditions, early and later in the day. In the…
Orthemis sibylla is shown to be a junior synonym of O. ambirufa, based on a comparison of the holotype male of O. ambirufa with voucher specimens in the UMMZ identified as O. sibylla by Ris and specimens of this species from French Guiana and Venezuela in the RWG collection. Diagnostic characters of the male holotype…