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…
Notogomphus maathaiae sp. nov. (holotype ♂: Kenya, Western Province, Mt Elgon District, Mt Elgon, Rongai River, 2,361 m a.s.l., 1°02′19.4″N, 34°45′20.5″E, 06 vi 2000) is described from a series of 8 males and 3 females collected at montane forest streams in Kenya. The status and biogeography of this and other montane species are discussed.
Sympetrum vicinum is a sit and wait predator, which takes off and pursues small flying insects during its long flying season (July to November). We investigated whether foraging individuals become less discriminating regarding prey size selection during the fall season because the changeable fall weather has an impact on the prey population. To investigate the…
Taxonomic and faunistic information is provided on the Anisoptera of Guangxi Zhuang Autonomous Region, China. The genus Atratothemis is established to receive a newly discovered libellulid species A. reelsi sp. nov. belonging to the subfamily Pantalinae. Oligoaeschna aquilonaris sp. nov., Periaeschna rotunda sp. nov., Petaliaeschna gerrhon sp. nov. and Asiagomphus giza sp. nov. are described.
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…
In the premontane rain forests of northwest Costa Rica, patches of secondary forest can contain high densities of large Vriesea spp. bromeliads. Such patches contain an average of 6,470 ± 1,080 (s.e.) larvae ha-1 of the bromeliad-dwelling pseudostigmatid, Mecistogaster modesta, ca 3 6× higher than larval densities that we previously reported for adjacent primary forest.
The larva of Mecistogaster linearis is described and illustrated from specimens collected within or near the Río Dantas Wildlife Refuge at the north-western border of the Barbilla National Park on the Costa Rican Caribbean slope. Characters of F-0 larvae permit easy separation from Megaloprepus caerulatus, a species coexisting with M. linearis. Diagnostic characters include overall…
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.