Genus Zosteraeschna Peters & Theischinger, 2011
highland hawkers

Synonyms:

  • scientific: formerly placed in genus Aeshna Fabricius, 1775

Type species: Aeshna ellioti Kirby, 1896

Introduction

The three species are confined to eastern and southern Africa. They are small (hindwing 36-41 mm) and dark brown, marked with yellow-green, but the apex of abdominal segment 2 and base of 3 are marked blue. Z. usambarica was formerly treated as subspecies of Z. ellioti: both breed in pools, typically in streams, which are usually shaded by highland forest, such as small impoundments. Z. minuscula from South Africa and Namibia has a similar but wider habitat range, found commonly at sheltered streams pools from sea level to highlands, but also at calm river sections, ornamental garden ponds and small dams. [Adapted from Dijkstra & Clausnitzer 2014]

Diagnosis

Male of genus is similar to Afroaeschna by (a) frons about ½ as wide as head; (b) vertex all dark and black mark on frons thick without pale encircling; (c) labium brown, eyes and face greenish; (d) R3 gradually curved backward near distal end of Pt; (e) IR2 extends at most halfway under Pt; (f) Hw cubital field always of 2 rows at base; (g) anal triangle almost reaches tornus; membranule large, bordering anal triangle for less than ½ its length; (h) genital lobe short and rounded, usually with denticles; (i) tips of cerci flat or rounded, not down-curved points; (j) epiproct less than ½ as long as cerci. However, differs by (1) smaller size, Hw 36-41 mm; (2) membranule blackish rather than pale grey, and with contrasting white base; (3) anal triangle of 3 rather than 2 cells; (4) dorsum of S10 without tooth; (5) apex of cerci flat, pointed, without denticles, rather than thickened, rounded with denticles on dorsum. [Adapted from Dijkstra & Clausnitzer 2014]


Zosteraeschna ellioti (Kirby, 1896). Male © Viola Clausnitzer


Zosteraeschna minuscula (McLachlan, 1895). Male © Gerhard Diedericks

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.


Reference

  • Peters, G. & Theischinger, G. 2011. The genera of the afrotropical "Aeshnini": Afroaeschna gen. nov., Pinheyschna gen. nov. and Zosteraeschna gen. nov., with the description of Pinheyschna waterstoni spec. nov. (Anisoptera: Aeshnidae). Odonatologica 40(3):227-249. [PDF file]

Citation: Dijkstra, K.-D.B (editor). African Dragonflies and Damselflies Online. http://addo.adu.org.za/ [2017-03-26].