Genus Hadrothemis Karsch, 1891
jungleskimmers

Synonyms:

• scientific: Archiclops Karsch, 1891 [infestus]; Nympheutria Karsch, 1894 [versuta]; Bolivarides Martin, 1907 [acuminatus = defecta]

Type species: Orthetrum camarense Kirby, 1889

Introduction

Seven species are endemic to tropical Africa. All are striking, robust and (fairly) large (hindwing 29-42 mm), although quite different in appearance, ranging from the smaller H. defecta and H. versuta, and the long-bodied H. infesta, to the very bulky H. coacta and H. scabrifrons. They are typical of forest, breeding in small bodies of standing water: rather open and marshy for H. defecta, large but more sheltered for H. infesta, small and deeply shaded for H. versuta, and bare puddles (typically on roads) for H. coacta. The genus includes the only African anisopterans known to breed in tree-holes and other phytotelmata: H. camarensis, as well as presumably the closely similar H. vrijdaghi, and H. scabrifrons. Adults of all species are encountered at sunny spots in forest clearings and edges, for instance along logging roads. During oviposition, hovering females rhythmically hit the water surface with abdomen tip, propelling eggs in drops of water up to a metre away onto the water’s banks. [Adapted from Dijkstra & Clausnitzer 2014]

Diagnosis

Male of genus is similar to Orthetrum and Nesciothemis by (a) size, Hw 22-50 mm; (b) distal Ax in Fw complete, extends across subcosta like proximal Ax; (c) Fw triangle of 1-4 cells, subtriangle of 3-5 cells [1-10]; (d) Fw discoidal field of 3-5 rows, if 2 at base then Fw supratriangle normally with 1-2 cross-veins; (e) 1-3 rows in radial planate; (f) 1 Cux in Hw; (g) anal loop usually long and boot-shaped with 10 or more cells; (h) hamule with prominent lobe than often dwarfs smaller hook; (i) if S7 marked, then this mark not or scarcely more prominent than that on S6. However, differs by (1) frons rounded rather than flattened, not ridged; (2) frons often with metallic blue or purple sheen, rather than glossy black; (4) wings often extensively marked; (5) 1-2 (rather than 1) Cux in Hw; (6) genital lobe small, truncate, usually directed towards hamule (rather than large or small, rounded, and directed away from hamule). [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

• Dijkstra, K.-D.B. (in prep.). Odonata of the Congo: checklist, bibliography, gazetteer, new records, species descriptions, and taxonomic notes with an emphasis on Elattoneura, Mesocnemis and Congothemis. Zoologische Mededelingen. [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.
• Pinhey, E.C.G. (1961). Dragonflies (Odonata) of Central Africa. Occasional Papers Rhodes-Livingstone Museum, 14, 1-97. [PDF file]
• Sjöstedt, Y. (1900). Odonaten aus Kamerun, West -Afrika. Beltrage Zur Kenntnis der insektenfauna von Kamerun. Binhang Kongliga Svenka VetenskapsAkademiens Handlingar, 25, 1-62.
• Martin, R. (1907). Odonates de la Guinée espagnole. Memorias Sociedad espanola Historia natural, 1, 421-432. [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/ [2024-10-30].