Coenagrion caerulescens (Fonscolombe, 1838)
Mediterranean Bluet

Type locality: SW Europe, no locality data available.

Diagnosis

Doppelganger of C. scitulum, favouring flowing rather than still waters, although it is relatively more common than its sibling in northern Africa. Details of the male appendages and female pronotum are the most reliable means of separating the two. Similar in size and shape to C. scitulum. The markings differ subtly from this species, although there is overlap and these characters cannot entirely be relied upon: (1) both sexes tend to have large, pale, paired spots on the pronotum (not small or absent); (2) males usually have more than half (not less) of S3-4 black, often with relatively more on S3 than S4 (not the reverse); (3) male S9 usually has some black (seldom unmarked blue). Females are not unlike C. scitulum (also with long pterostigmas), but are generally very pale with broad antehumeral stripes (wider than the black stripe below it), larger postocular spots and narrower black markings on abdominal upperside than congeners. In most of its range, they have the abdomen tip (S9-10 and appendages) largely blue, not black on top as in overlapping Coenagrion species, including C. scitulum. See C. scitulum for shared features which differ from other Coenagrion. Outer corner of the pterostigma is more acute than in C. scitulum (i.e. pterostigma appears more triangular than quadrangular). Male upper appendages are longer and straighter than in C. scitulum, only weakly hooked at tips and over half as long as S10. Female is instantly recognisable by the pale projecting ‘V’ in the hind margin of the pronotum. Male pronotal margin has a small knob in the middle. [Adapted from Dijkstra & Lewington 2006]

Habitat description

Mostly streams, but also rivers and headwaters, in open landscapes. Usually with emergent and often aquatic vegetation. From 0 to 2100 m above sea level, but mostly below 1100, although possibly up to 2900.

Distribution

confirmed: Algeria; Libya; Morocco; Tunisia

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

  • de Fonscolombe, M.B. (1838). Annales Societe Entomologique France, 7, 547-575.

Citation: Dijkstra, K.-D.B (editor). African Dragonflies and Damselflies Online. http://addo.adu.org.za/ [2021-12-05].