It has been shown that life history, behavioural as well as morphological traits vary with the habitats occupied by odonate larvae. Here we ask the following questions: (1) Are the morphological traits, which are associated with perception and foraging, related to the larval habitat? (2) Do these traits influence foraging success and growth rate? We…
Elasmothemis rufa sp. nov. (holotype: Venezuela, Amazonas, Río Cataniapo), Macrotbemis taurepan sp. nov. (holotype: Venezuela, Bolívar, El Paují), and Oligoclada garrisoni sp. nov. (holotype: Venezuela: Amazonas, San Fernando de Atabapo) are described and illustrated. All holotypes are deposited at MIZA. Macrothemis heteronycha and Micrathyria paruensis are recorded from Venezuela for the first time, and Micrathyria…
For eleven species of sympatric libellulids, male mean mass was positively correlated with wing aspect ratio, wing loading, and mean perch height. We tested the hypotheses that perch height selection was governed by interspecific competition or biomechanical responses to increased wind speed at higher perches. Although larger odonates might prefer higher perches to offset their…
Chalybeothemis chini sp. nov. from Pahang, Peninsular Malaysia, and C. pruinosa sp. nov. from Sarawak, Malaysian Borneo, are described from the male sex. The new species necessitate some redefinition of the previously monotypic genus, which is provided. The quiescent penis of Chalybeothemis is illustrated for the first time. Differences between C. chini, C. fluviatilis and…
Ten common libellulid species perch along the shoreline of lakes and ponds in South Carolina, USA. We collected individuals at five ponds throughout summer 2005, weighed them in the field, and calculated wing loading (N·m2) and wing aspect ratios from digital photographs. We measured the perch-height preferences of these species in ‘low perch’ (10, 20,…
Egg size differences might have an important influence on reproductive success because they may lead to different offspring conditions, hatching date or larval size. We presumed that egg size in odonates positively correlates with egg development time, and larger eggs lead to larger larvae. However, we assumed that the size benefit could only be maintained…
The small African species of Diplacodes have been confused for a long time, in part because the black mature males are difficult to separate. The holotype of D. deminuta belongs to the species commonly known as D. okavangoensis, the former name taking priority, while its paratypes belong to that known erroneously as D. deminuta, which…
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…
The Afrotropical ‘neodythemistine’ genera are an example of venation-biased classification in Odonata. This example is used to argue the bankruptcy of some traditional classifications in the order, particularly in the Libellulidae, and the need to apply alternative characters to define genera. Two groups of Afrotropical ‘neodythemistines’ are identified by male and female genitalia, supported by…
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…