A contribution to the study of the Odonata fauna of Palau (Insecta: Odonata)

The Odonata fauna of Palau is reviewed based on all published records and new data collected during the last 25 years. The list of scientific names of taxa is updated and analysed. At least two new taxa at generic level are added based on females which could not be associated with any of the males so far reported for Palau: Pericnemis (?) Selys, 1863 proposed as a provisional scientific name for two females which were found to be closer to congenors from the Philippines, and Gynacantha Rambur, 1842 based on one female. The updated faunistic list is accompanied by photos of live individuals and diagnostic photos of specimens of all presently known members of the included taxa. Priorities in faunistic and taxonomic studies are suggested, with a focus on phenology and habitat requirements, especially of the Palau endemics Pseudagrion palauense Lieftinck, 1962; Teinobasis palauensis Lieftinck, 1962; Drepanosticta palauensis Lieftinck, 1962 and Agrionoptera cardinalis Lieftinck, 1962. The latter is discussed in the faunistic account, with description of the exuvia (by supposition) which is proposed for first time. The three other endemics are illustrated with detailed photos of diagnostic features. Short biogeographic notes are included as well, highlighting the significance of the islands within the Republic of Palau.