I compared males of Leucorrhinia intacta collected at two permanent and two previously dried ponds to assess whether males colonizing formerly dried sites differed in morphology or level of mite parasitism from males at permanent sites. Males colonizing sites that had local extinctions in the previous year due to pond drying were more similar to…
We compiled data on the occurrence and frequency of distinct female variants among Holarctic Odonata and interpreted the data in light of harassment-based hypotheses. The major source of male confusion for male mimicry hypotheses is predicted to be signal similarity between andromorphs and male distractors; for the learned mate recognition hypothesis (LMR), it is predicted…
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…
Heteragrion makiritare sp. nov. is described from two males from the Pantepui region – holotype: Venezuela, Amazonas State, Marahuaka, Sima (3°43′N, 65°31′W), 1,140 m a.s.l., MIZA, no. 17250. It belongs in the species group whose paraprocts are absent in the male sex. The identity of H. macilentum is elucidated by examining its lectotype and a…
The morphology of the hitherto unknown female of Somatochlora borisi is described and illustrated basing upon eight adults from Bulgaria, Greece and Turkey. A key is provided which allows the determination of the females of all West Palaearctic Cordulia and Somatochlora spp. A list of the presently known localities and a distribution map show the…
This study records 175 species of odonates from Brunei, representing more than half the known Bornean fauna. Of these, 169 species were collected by the author and associates using a systematic sampling protocol at 35 sites throughout the country. Sites were located in diverse habitats: in primary forest, natural lakes and marshes and degraded areas.
It is often assumed that males do not choose among females because competition for partners is high and male mating costs are low. Nevertheless, this assumption does not always hold. In some species duration of copulation is long, possibly causing a limitation on the lifetime number of matings for males. In this case we expect…
Male aeshnid dragonflies at a small pond (circumference ca 90 m) in Cambridgeshire U.K. generally pursued males of other aeshnid species as well as their own. As a result of these encounters the pursued insect frequently left the pond, particularly when it belonged to a smaller species. Libellulids, which differed greatly from the aeshnids in…
This paper is dedicated to Philip S. Corbet on the occasion of his 70th birthday.
This paper is dedicated to Philip S. Corbet on the occasion of his 70th birthday.