Genus Hemicordulia Selys, 1870
island emeralds

Type species: Cordulia australiae Rambur, 1842

Introduction

Of over 50 species, most occur in Australia and New Guinea, from where the genus extends across the Pacific and Indian Oceans to Africa: one species each inhabits Mauritius and Réunion, and one Madagascar and the Seychelles. H. africana occurs from southern Uganda, through western Tanzania and northern Malawi to north-eastern South Africa. It was long believed to be the same as H. asiatica from India, but is closest to the Madagascan H. similis. It is an elusive inhabitant of swampy forests, found hawking along edges and in glades mostly at dusk or with overcast weather. The species is medium-sized (hindwing 27-32 mm) and metallic dark green with indistinct warm yellow markings in the face and the sides of thorax and abdomen, most clearly on abdominal segments 6-8. [Adapted from Dijkstra & Clausnitzer 2014]

Diagnosis

Male of genus is similar to Neophya by (a) posterior border of eyes arched prominently at about midheight; (b) wings with 1 Cux; supratriangles without cross-veins; (c) Hw arculus aligned with proximal border of triangle, sometimes just proximal or distal to it; (d) anterior side of tibiae (at least on hind legs) with longitudinal ridge-like keels; (e) S2-4 all without transverse ridge. However, differs by (1) larger size, Hw 27-32 mm; (2) Fw discoidal cell (‘triangle’) triangular rather than quadrangular; (3) discoidal field in both wings of 2 or more rows; (4) Rspl present; anal triangle absent; (5) sectors of arculus only fused at their origin. [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.

References

• Fraser, F.C. (1949). Notes on the Odonata of Mauritius 1. The genus Hemicordulia Sélys. Proceedings of the Royal Entomological Society of London (B), 18, 130-134. [PDF file]
• Dijkstra, K.-D.B. (2007). Gone with the wind: westward dispersal across the Indian Ocean and island speciation in Hemicordulia dragonflies (Odonata: Corduliidae). Zootaxa, 1438, 27-48. [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.

Citation: Dijkstra, K.-D.B (editor). African Dragonflies and Damselflies Online. http://addo.adu.org.za/ [2024-11-15].