Genus Diplacodes Kirby, 1889
- scientific: Philonomon FÃ¶rster, 1906 [erlangeri = luminans]
Type species: Libellula tetra Rambur, 1842 [= D. lefebvrii (Rambur, 1842)]
The genus ranges from Africa through southern Eurasia to Australia and the Pacific. There are ten species, five of which occur in open marshes in Africa and Madagascar, while an Asian species reaches the Seychelles. D. luminans is widespread, preferring seasonal marsh, while D. lefebvrii can be found at virtually every open marsh in the continent. The two small species, however, are localised. They may occur together, although D. pumila tends towards smaller, more elevated and especially boggy marshes from Katanga to South Africa; D. deminuta is very widespread but only really common in the Okavango Delta and was indeed known as D. okavangoensis for many years. With Palpopleura jucunda the two are probably the smallest African anisopterans. The medium-sized D. luminans was previously placed in the monotypic genus Philonomon. It is easily distinguished by its abdomen with red base and black yellow-spotted end. Identification of the closely similar smaller species becomes difficult when the males age and blacken completely, obscuring diagnostic markings. Mature D. deminuta males may appear notably grey due to pruinosity. Characters for young males also suffice to identify females. [Adapted from Dijkstra & Clausnitzer 2014]
Male of genus is similar to Eleuthemis by (a) frons and vertex of different colour (e.g. brown or red), more uniform (e.g. less contrasting yellowish dorsally and brown ventrally), or dorsum darkest; (b) occipital triangle smaller with rather concave borders, eyes touching over distance of at least half its length; (c) face quite uniformly dull yellow, red, brown or black; (d) Pt never black-and-white and wings at most with dark tips or bases or with overall yellowish infusion; (e) Fw supratriangles without cross-veins; (f) Fw triangle of 1 cell; (g) Fw discoidal field of 1-2 cell-rows at base, sometimes 3; (h) 6½-10½ Ax in Fw; (i) Hw arculus in line with proximal border of triangle, sometimes just proximal or distal; (j) S1 without ventral process. However, differs by (1) arculus between Ax1-2, often closest to Ax1; (2) subtriangle of 2-3 (rather than 1) cells; (3) Abd slender rather than broad, S3-7 each longer than wide, ventrally similarly coloured as dorsum. [Adapted from Dijkstra & Clausnitzer 2014; this diagnosis not yet verified by author]
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. (1976). Dragonflies (Odonata) of Botswana, with ecological notes. Occasional Papers of the National Museums and Monuments of Rhodesia Natural Sciences, 5, 524-601. [PDF file]
- Dijkstra, K.-D.B. (2006). African Diplacodes: the status of the small species and the genus Philonomon (Odonata: Libellulidae). International Journal of Odonatology, 9, 119-132. [PDF file]
- 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.
- 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]
- Lieftinck, M.A. (1969). Odonates Anisoptères - Odonata Anisoptera. Explor. hydrob. Lac Bangweolo and Luapula, 14, 1-64. [PDF file]
Citation: Dijkstra, K.-D.B (editor). African Dragonflies and Damselflies Online. http://addo.adu.org.za/ [2021-01-23].