In a large population of Lestes viridis inhabiting a complex, extended system of channels in the floodplain of the Upper Rhine River near Weisweil (Baden-Württemberg, Germany) detailed samples of exuviae were collected from several subpopulations. For each sample the sex ratio was determined. For statistical reasons only samples with at least 700 exuviae were considered.
The large Neotropical zygopterans Megaloprepus caerulatus, Mecistogaster linearis and M. ornata (Pesudostigmatidae) were surveyed during five years, and striking differences in their reproduction patterns were shown: (1) At two study sites in seasonal, tropical semi-dry forests in Pacific Costa Rica, adult M. ornata could be observed throughout the year, occasionally during the dry season up…
Neurobasis awamena, a new calopterygid species from the southern highlands of New Guinea (holotype: Pimaga area, 6°30′S, 143°30′E, 27 vii 1994, deposited at Naturalis, Leiden) is described and figured. It is distinguished from the widespread N. australis by its longer legs, irregular teeth on the male cerci, and the sharp demarcation of the iridescent color…
The first known amphipterygid-like zygopteran from amber is described. Although its provenance is not known with certainty, we feel confident in attributing it to the Baltic amber deposits of northern Europe. It thus represents the first Old World Tertiary amphipterygidan and substantially extends the known geographic range of the taxon. Based on current knowledge its…
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…
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…
Japan is a small country but ranges from the subtropical to the subarctic zone. Every year during spring to autumn, many typhoons bring tropical taxa, which occasionally establish in Japan. Up to now, 215 odonate taxa have been recorded, 34 of which are regarded as critical species. Intensive research on Odonata – supported by identification…
The Philippine odonate fauna is characterized by a high percentage of endemic species, especially in Zygoptera, most of which have a very limited range. Due to the continuing loss of forests and other habitat destruction, a majority of the 300 plus known species could be red-listed, but only a few critical species are evaluated here.
A terminology is presented for structures and events in larval development of Odonata with the aim of bringing terms into conformity with those used for other insect orders in the light of accepted views of homology. The terms ‘exuvia’, ‘larva’, ‘prolarva’ and ‘stadium’ receive special mention. Records of the number of stadia required to complete…
Predation of aggregated, ovipositing tandems of Sympetrum sanguineum and S. vulgatum by the hornet Vespa crabro was observed in Belarus. The same species of hornet was seen killing territorial males and copulating females of Calopteryx haemorrhoidalis in Italy. Numerous remains of these odonates at the oviposition sites suggest that attacks occur frequently. A short review…