Onychogomphus costae (Selys, 1885)
Type locality: Oran, Algeria
Small, odd-looking western Mediterranean Onychogomphus, whose body has different shades of ivory, ochre and rust but is almost devoid of black. Easily overlooked due to its small size and camouflaging coloration. Smallest and palest Onychogomphus. Easily told from congeners by size, pallid but warm brown ground-colour and the absence of large, distinct black markings. It is the only Onychogomphus within its range with a beige rather than dark-brown to black pterostigma. Resembles Paragomphus genei in size, posture, pale pterostigma and indistinct markings, but latter has a green face and thorax, more abdominal black and broad flaps on S8-9 in the male (appendages also differ). Appendages are slender and very distinct from other Onychogomphus. The lower is much shorter than the uppers, are elongate and without knobs or teeth. The appendage is deeply incised (view from below), the two branches widely diverging. In other Onychogomphus the branches are close and parallel; in O. forcipatus and O. uncatus they bear subbasal knobs. Males have long whitish hairs at the base of the underside of S7, which are 3-4 times as long as those on S6. [Adapted from Dijkstra & Lewington 2006]
Mostly rivers, but also streams, in open landscapes. Often faster sections with bare banks, rocks and a gravelly and/or sandy bottom. From 0 to 2100 m above sea level.
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.
- de Sélys-Longchamps, E. (1885). Rectification concernant l'Onychogomphus genei Selys, et signalement de deux gomphines nouvelles. Annales Societe Entomologique Belgique, 29, 8.
Citation: Dijkstra, K.-D.B (editor). African Dragonflies and Damselflies Online. http://addo.adu.org.za/ [2021-01-27].