Genus Proischnura Kennedy, 1920
fork-tailed bluets
Synonyms:
- scientific: formerly placed in genus Enallagma Charpentier, 1840
Type species: Enallagma subfurcatum Selys, 1876
Introduction
Endemic to Africa, the genus was formerly classified as part of Enallagma. The three small (hindwing 12-18 mm) species superficially recall Ischnura but are less black overall, have long splayed cerci, and black pterostigmas with at most a narrow whitish rim. The tiny and dark purple P. polychromatica is currently known from only two areas in the Western Cape, P. rotundipennis is confined to South Africa’s highveld, while the numerous bluets found at marshy spots in most mountainous areas of tropical Africa are usually P. subfurcata. Habitats typically have dense vegetation (grass, moss) and very shallow water. The best sites not only warm up quickly, but also have a slight current, e.g. boggy runnels or dense mats of floating vegetation along streams. [Adapted from Dijkstra & Clausnitzer 2014]
Diagnosis
Genus similar to Africallagma by (a) mesostigmal plates (narrow plate anterior to mesepisterna immediately posterior to prothorax) dorsally with raised flap- or knob-like ridges; (b) humeral stripe at most 2x as wide as antehumeral stripe; (c) Pt in Fw and Hw similarly coloured, brown to black; (f) base of paraproct usually much swollen, resulting in prominent inferior bulge. However, differs by (1) cerci with rounded, swollen upper branch and pointed lower branch, separated by shallow notch (lateral view). [Adapted from Dijkstra & Clausnitzer 2014]
Proischnura subfurcata (Selys, 1876). Male © Hans-Joachim Clausnitzer
Proischnura polychromatica (Barnard, 1937). Female © Hennie de Klerk
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.
References
- May, M.L., and Dijkstra, K.-D.B. (in prep). Keys and distributional data for African damselflies of the genera Africallagma, Azuragrion, Pinheyagrion and Proischnura, with taxonomic notes and the description of a new species of Africallagma. Zoologische Mededelingen. [PDF file]
- Ris, F. (1921). The Odonata or Dragonflies of South Africa. Annals South African Museum, XVIII, 245-452. [PDF file]
Citation: Dijkstra, K.-D.B (editor). African Dragonflies and Damselflies Online. http://addo.adu.org.za/ [2024-11-15].
