Genus Anaciaeschna Selys, 1878
Type species: Anaciaeschna jaspidea Burmeister, 1839
The genus owes its scientific name to its combination of venation characters of both Anax and Aeshna, the latter now split into three genera in tropical Africa. Seven species range from southern Asia to the Pacific, while A. triangulifera is rather thinly spread in eastern and southern Africa and Madagascar. It is encountered mostly in forest, from highlands down to sea-level. It probably breeds in standing water and, as its vernacular name indicates, adults are most active at dusk. They recall Zosteraeschna ellioti or Z. usambarica in the field, but are medium-sized (hindwing 41-45 mm) and the male’s face is bluish white, the eyes are bright blue in life (but brown when young), and the small abdomen spots are also bluish. Green markings and eyes predominate in similar-sized African aeshnid males. [Adapted from Dijkstra & Clausnitzer 2014]
Male of genus is similar to Pinheyschna by (a) frons about ½ as wide as head; (b) auricles present; (c) IR3 clearly forked proximal to Pt; IR2 extends at most halfway under Pt; (d) R3 not or only weakly arched forward near distal end of Pt; (e) distal end of Rspl directed at wing tip or point posterior of it; anal triangle present; (f) membranule large, broadly bordering anal triangle; (g) Hw tornus angled, and Hw cubital field always of 2 rows at base; (h) anal triangle almost reaches tornus. However, differs by (1) vertex with 2 pale spots; stem of black mark on frons is broad triangle; (2) eyes bright blue rather than greenish in life; (3) R3 fairly abruptly arched forward near distal end of Pt, rather than gradually curved backward near distal end of Pt; (4) membranule borders anal triangle for more, rather than less, than ½ its length. [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.
- 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/ [2021-01-20].