Genus Porpax Karsch, 1896
Type species: Porpax asperipes Karsch, 1896
Endemic to tropical Africa, the six known species are generally localised at habitats with much organic material. P. risi lives in open highland marshes and bogs, the other species in forest: P. asperipes occurs at swampy streams and seeps, P. bipunctus favours soaked leaf litter (e.g. on seeps or beside streams) and avoids open water, and P. sentipes has been found by dried-up depressions filled with dead leaves. The related P. garambensis and P. mezierei have overlapping ranges, inhabiting similar blackwater swamps and pools, but the former prefers deeply shaded sites with only small sun spots, while the latter occurs on the forest edge. Males of the forest species sit low in sunspots, perching flat on leaves, and fly up quickly when disturbed or when sunshine disappears. Because of this behaviour and their specific habitats, the forest species are easily overlooked. All species are fairly small (hindwing 21-29 mm), cute black dragonflies with contrasting yellow, green and turquoise markings, easily recognised by their boldly banded faces and, in most species, a pale ring on abdominal segment 6: such a marking normally lies on segment 7 in Anisoptera. The species have similar appendages and genitalia, but differ in markings and femoral ornamentation. [Adapted from Dijkstra & Clausnitzer 2014]
Male of genus may recall Acisoma by (a) small size, Hw 19-29 mm; (b) head, thorax and Abd with fragmented white, yellow, green or turquoise markings; (c) frons and vertex ventrally black, dorsally usually with contrasting white, greenish or blue markings; (d) occipital triangle large with rather straight borders, eyes at most touching over distance less than half its length; (e) distal Ax in Fw incomplete, its subcostal section absent (indicated as ‘½’ when Ax are counted); (f) 1 cell-row in radial planate; (g) Hw at most with small dark patch at extreme base. However, differs by (1) 8½-14½ Ax in Fw; (2) Fw triangle of 2 cells and subtriangle of 2-3, both only rarely just 1; (3) arculus at least in Hw distal to Ax2; (4) 2-3 Cux in Hw, but rarely 1-4; (5) Abd of normal shape, rather than swollen at base, and may become pruinose; (6) S4 without transverse ridge. [Adapted from Dijkstra & Clausnitzer 2014]
Map citation: Clausnitzer, V., K.-D.B. Dijkstra, R. Koch, J.-P. Boudot, W.R.T. Darwall, J. Kipping, B. Samraoui, M.J. Samways, J.P. Simaika & F. Suhling, 2012. Focus on African Freshwaters: hotspots of dragonfly diversity and conservation concern. Frontiers in Ecology and the Environment 10: 129-134.
- Pinhey, E. (1966). Odonata. Mission H. de Saeger, Exploration du Parc National de la Garamba, 45, 1-114.
- Dijkstra, K.-D.B. (2006). Taxonomy and biogeography of Porpax, a dragonfly genus centred in the Congo Basin (Odonata, Libellulidae). Tijdschrift voor Entomologie, 149, 71-88. [PDF file]
- Ris, F. (1921). The Odonata or Dragonflies of South Africa. Annals South African Museum, XVIII, 245-452. [PDF file]
- Pinhey, E.C.G. (1961). Dragonflies (Odonata) of Central Africa. Occasional Papers Rhodes-Livingstone Museum, 14, 1-97. [PDF file]
- Schouteden, H. (1934). Annales Musee Congo belge Zoologie 3 Section 2, 3, 1-84. [PDF file]
Citation: Dijkstra, K.-D.B (editor). African Dragonflies and Damselflies Online. http://addo.adu.org.za/ [2017-12-12].