Nesobasis species diversity and abundance: notes on an endemic genus of the island group of Fiji (Zygoptera: Coenagrionidae)

Compared to other regions in the world, the islands scattered over the south-western Pacific Ocean remain largely unstudied with respect to damselfly biology. Only a few studies have been undertaken and these have been mainly of a taxonomic nature. Here, an overview is presented of the diversity, abundance, distribution and field diagnostic characteristics of spp. within the Fijian genus Nesobasis, one of the most speciose odonate genera found in any oceanic island group in the world. 24 spp. (2 undescribed) were encountered during a 2-month visit in the dry season of 2005, collected from Viti Levu and Vanua Levu. This brings the total number of spp. currently known for the genus to 31 (of which only 21 are at present formally described). Information is provided on species diversity and abundances at the major collecting sites. For both islands the most speciose location harboured 8 spp. Abundant spp. tended to be widespread, while less abundant spp. were usually restricted in occurrence to a few sites. Included are basic species descriptions and observations on reproductive activities.