Genus Notiothemis Ris, 1919
forestwatchers

Type species: Notiothemis jonesi Ris, 1919

Introduction

Endemic to tropical Africa with two species. Their appearance and behaviour recalls Tetrathemis: small (hindwing 20- 25 mm) black dragonflies with clear-cut greenish markings that favour small shaded bodies of water. They especially like pools in or by forest streams, perching low above the surface and often in full shade, escaping upwards at the slightest disturbance. Eggs are laid on material above the water surface, but unlike Tetrathemis this happens in flight. The two species only occur together from western Kenya through Uganda to western Tanzania, and are easily separated through binoculars by the markings on the front of the thorax. [Adapted from Dijkstra & Clausnitzer 2014]

Diagnosis

Male of genus is similar to Tetrathemis by (a) size,with Hw 20-31 mm; (b) Fw discoidal field of 1 cell-row at base; (c) Fw supratriangle with 1-2 cross-veins [0-2]; (d) Fw triangle and subtriangle usually of 1 cell, rarely both 2; (e) Fw discoidal field of 1-2 rows at base; (f) always 1 cell-row in radial planate; (g) triangles (may appear quadrangular in shape) in all wings without cross-veins; (h) bridge spaces with 1 crossvein [1-2]; (i) 7-11 Ax in Fw; (j) 2-4 Cux in Hw; (k) anterior denticles on hind femora wide distally, square-cut or directed towards base; (l) hamule with small, blunt, fingerlike or concealed hook; (m) hamule without longitudinal ridge, with hook bent outwards, well visible in lateral view; (n) S7 with conspicuous pale mark, which is more prominent than any marking on S6 (invisible when covered by pruinosity). However, differs by (1) dorsum of frons pale rather than shiny black, with black basal band; (2) Fw discoidal field becomes 2 cell-rows before node; (3) Fw triangle three-sided rather than quadrangular; (4) vein separating Fw cubital space and subtriangle in line with anterior border of triangle; (5) 2-4 Cux in Hw. [Adapted from Dijkstra & Clausnitzer 2014; this diagnosis not yet verified by author]


Notiothemis jonesi Ris, 1919. © Warwick Tarboton


Notiothemis robertsi Fraser, 1944. Male © Jens Kipping

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. (1944). A note on the genus Notiothemis Ris, with the description of a new species (Order Odonata). Proceedings of the Royal Entomological Society of London (B), 13, 40-43. [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]

Citation: Dijkstra, K.-D.B (editor). African Dragonflies and Damselflies Online. http://addo.adu.org.za/ [2017-08-19].