Genus Selysiothemis Ris, 1897
black pennants
Type species: Libellula nigra Vander Linden, 1825
Introduction
Monotypic genus that may better be merged with Macrodiplax. S. nigra occurs in arid and coastal regions around the Mediterranean Sea, and from central Asia to northern Africa. It breeds in (often ephemeral) ponds and lakes, and may patrol tirelessly over water, hover above the ground, or perch at the end of stakes with raised wings fluttering in the wind. Males are medium-sized (hindwing 24-28 mm) and turn totally black with maturity, obscuring initially extensive buff markings. They are easily identified by their open and almost translucent venation, the short pale pterostigmas with contrasting black veins, recalling an ‘equals sign’. [Adapted from Dijkstra & Clausnitzer 2014]
Diagnosis
Male of genus is similar to Aethriamanta by (a) Fw triangle always of 1 cell, subtriangle 1-3; (b) Fw discoidal field of 2 cell-rows at base; (c) 6 Ax in Fw [6-7]; (d) subtriangle of 1 cell; (e) distal Ax in Fw complete, extends across subcosta like proximal Ax; (f) arculus in all wings usually closer to Ax1 than Ax2; (g) sectors of arculus in Fw often separate at or just distal to arculus; (h) Hw base not so broad, cells evenly proportioned, and base with large dark patch; (i) S4 without transverse ridge, although colour pattern or scar-like seam may indicate its position, there is no ridge of similar magnitude as transverse ridge of S3 and lateral carina of S4. However, differs by (1) venation pale rather than dark; (2) Hw base clear rather than amber with dark subcostal and cubital streaks; (3) hamule about as long as genital lobe; (4) Abd black rather than red with maturity. [Adapted from Dijkstra & Clausnitzer 2014; this diagnosis not yet verified by author]
Selysiothemis nigra (Vander Linden, 1825). Female © Jean-Pierre Boudot
Selysiothemis nigra (Vander Linden, 1825). Male © Jean-Pierre Boudot
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
- Dijkstra, K.-D.B., and Lewington, R. (2006). Field guide to the Dragonflies of Britain and Europe. British Wildlife Publishing, 1-320.
- Dijkstra, K.-D.B, and Clausnitzer, V. (2014). The Dragonflies and Damselflies of Eastern Africa: handbook for all Odonata from Sudan to Zimbabwe. Studies in Afrotropical Zoology, 298, 1-264.
Citation: Dijkstra, K.-D.B (editor). African Dragonflies and Damselflies Online. http://addo.adu.org.za/ [2024-05-20].