Taxonomy and biogeography of Porpax, a dragonfly genus centred in the Congo Basin (Odonata, Libellulidae)

Abstract

The tropical African genus Porpax is revised, five species are recognised, including the new species P. sentipes from Congo-Kinshasa. All species are fully diagnosed for both sexes and new records are included. A key to the species and illustrations of important characters are provided. The peculiarities of the genus are discussed, but little is known of its ecology. P. garambensis and P. sentipes sp. n. are confined to the Congo Basin, while P. asperipes is also present in the adjacent Lower Guinean forest. P. risi is spread out across highlands in south-central Africa. P. bipunctus is known from four disjunct rainforest regions from Liberia to eastern Congo and has different markings in each region. This distribution coincides with Africa's main rainforest refugia and is the best example of such disjunction seen in Afrotropical Odonata so far. The species' isolation appears to be linked to an ephemeral habitat, confining it to areas with perennial and predictable rainfall.