Palaeosynthemis nigrostigma sp. nov., a new dragonfly from Papua New Guinea (Anisoptera: Synthemistidae)

A new species of the synthemistid genus Palaeosynthemis is described from the Trauna River valley in Western Highlands Province, Papua New Guinea. The new species is most similar to P. cyrene from which it can be distinguished, among other characters, by the coloration of the pterostigma (jet-black in the new species vs brownish yellow in P. cyrene) and of the wing bases (not darkened vs strongly darkened). The new species also differs from P. cyrene in having a narrow, almost parallel-sided yellow lateral synthoracic stripe and a well-defined yellow marking along most of the ventral margin of the metepimeron. In P. cyrene the lateral synthoracic stripe is markedly wider and tapered, and the yellow element along the ventral margin of the metepimeron is absent. Characters of the adult male are illustrated and the affinities of the species are discussed.