The reproductive behaviour of Libellago semiopaca was studied on a swift-flowing shallow forest stream in Brunei. Females oviposited just below the water-line, commonly in groups, only on large, firm-textured, semi-submerged logs, usually guarded by males. Both sexes were very sedentary. Suitable sites, with good illumination and deep deposits of fine gravel and leaf mulch in…
The Odonata fauna of Papua New Guinea is species-rich, but human population growth and resulting modification of primary rainforests may lead to a loss of valuable habitat and species diversity. In this study, I compared the odonate assemblages of a natural tropical rainforest and a modified forest in order to assess the loss that could…
Quantitative data are essential for many aspects of ecological research. Several methods exist to quantify odonate abundance, but complications may arise when abundances in different habitats need to be compared. In this study, I explored a technique that can overcome the variable detectability of odonates in habitats with different visibility. Distance sampling is briefly introduced…
I sampled odonates in pristine lower montane rainforest in Papua New Guinea over several months, recording habitat characteristics for all encounters with adult odonates. Using ordination techniques such as cluster analysis and canonical correspondence analysis I then classified the odonate fauna into assemblages correlated with environmental factors. Within the 2.5 km2 study area I found…
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…
We compared the larval abundance of Mecistogaster modesta between bromeliads at ground level and canopy level in a primary tropical wet forest. Zygopteran abundance correlated strongly with bromeliad diameter at both levels. Although the per-bromeliad zygopteran abundance did not differ between vertical levels, M. modesta showed a strong vertical distribution in abundance owing to the…
Papuagrion carcharodon, a new coenagrionid from the rainforest of Papua New Guinea’s Simbu Province, is described (holotype: 06°43′S, 145°05′E; 900 m a.s.l., 27 March 2004, to be deposited at Naturalis, Leiden). This new species is similar to P. ekari and P. pesechem but may be distinguished from both by the tooth-shaped lower branch of the…
Western Africa—defined as the tropical area from Cameroon westwards—probably has the richest odonate fauna in Africa, particularly the region of (and around) the Cameroon highlands. This region is home to many relict and endemic species, such as the continent’s only representatives of the families Amphipterygidae and Perilestidae. Previous selections of threatened West African Odonata have…
Madagascar has approximately 175 species of Odonata. Of the Anisoptera ca 60% is endemic and of the Zygoptera almost 95%. The endemic species can roughly be separated into ‘new endemics’ that are probably recent arrivals from the African mainland and ‘old endemics’. The latter group includes many members of the families Megapodagrionidae, Platycnemididae and Corduliidae,…
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.