Status of the Systematic Knowledge and Priorities in Ephemeroptera Studies: the Oriental Region

Abstract

Of the 28 families containing about 400 genera and approximately 3,000 species of extant Ephemeroptera, 19 families, 104 genera (47 of these endemic) and more than 535 species have been described from the Oriental region including its transition zones (Afghanistan, Himalaya, China, and Papua-New Guinea). The families Baetidae, Heptageniidae and Leptophlebiidae exhibit the greatest diversity in this region. Mayfly diversity and distribution are briefly reviewed at the generic level based on the literature. However, our knowledge of Oriental mayflies seems to be fragmentary since most species are known only in either the larval (about 35%) or adult stage (about 39%); the total number of species is estimated to be at least 3–4 times higher. With few exceptions (e.g. Sri Lanka, Hong Kong, and the Sunda Islands), there are no detailed data on local faunas, biogeography, ecology and life cycles. Further taxonomic research, association of larvae and adults previously described separately, revision of available type material, detailed revisions of genera or species-groups, studies of faunas of defined regions (however small), biogeographic analysis including definition of the limits of the Oriental region, and intensive study of mayfly biology are the main research priorities discussed in this paper.