Genus Elattoneura Cowley, 1935
African threadtails

Synonyms:

• scientific: formerly placed in genus Prodasineura Cowley, 1934

Type species: Disparoneura glauca Selys, 1860

Introduction

Close to 70 species found in tropical Africa and Asia (but not Madagascar) have been placed in the genera Elattoneura and Prodasineura. Although species from both continents have been assigned to both genera based on the relative length of the anal vein, genetic research indicates that all African species are more closely related to each other than to any Asian species. The traditional genera thus are not natural groups and all African species are best grouped in one genus, Elattoneura, with Prodasineura restricted to Asia. There are probably at least 30 species in Africa; all fairly small (hindwing 15-22 mm), finely built damselflies. Males are pale with black markings at emergence, but become largely black with patches of white to grey pruinosity or bright colour (white, yellow, orange, or red) on face, thorax and/or abdomen tip. These colours stand out as males hover low above water in their gloomy habitats. Most species favour sheltered spots along running waters.

Although they may seek out shady spots, the species of the glauca-group with pruinose faces and mostly bluish eyes (E. cellularis, E. frenulata, E. glauca, E. nigra, E. pasquinii and E. tarbotonorum) occupy streams and rivers in rather open terrain, such as woodland, savanna, fynbos and grassland. E. lapidaria was only discovered in 2013 at streams at 1500-1600 m in the Chimanimani Mts of eastern Zimbabwe. It occurs with E. glauca, but perches only on reflective rocks, ensuring it stays warm in its often misty habitat.

The remainder (black or coloured faces) inhabit forested streams, those favoured by E. aurifex, E. tsiamae and E. vrijdaghi tending to be more open and sandy, while the others prefer deep shade: E. balli and E. lliba occur on most streams and small rivers in their range, while E. josemorai and E. pruinosa prefer smaller and often rockier streams, E. girardi and possibly E. lindleyi (small) rivers, and E. acuta, E. centrafricana, E. incerta, E. morini, E. villiersi and E. vittata prefer sluggish water with more mud and leaf litter, the latter species (which is a species-complex; name likely to change) especially liking seeps.

The genus is in need of taxonomic revision (for example E. balli and E. lliba may be a species complex that includes E. mayombensis, while E. josemorai and E. pruinosa may be synonymous) and effectively nothing is known of E. dorsalis, E. flavifacies, E. odzalae, E. perisi and E. pluotae. Identification should be based on mature living males, as coloration and pruinosity change with maturation and are sometimes lost in preservation. It is also aided by examination of the penis. [Adapted from Dijkstra & Clausnitzer 2014]

Diagnosis

Male of genus is similar to Proplatycnemis and Copera, by (a) head very wide, about 3x as broad as deep; (b) wings clear; (c) quadrilaterals rectangular, in Fw anterior border about 3x as long as distal border; (d) 2 cells betweenquadrilateral and subnode [2-3]; (e) Cux stands distal from origin of anal vein by about its own length; (f) IR3 originates closer to subnode than R4. However, differs by (1) anal vein terminates level to distal border of quadrilateral; (2) legs largely black, rarely red, tibiae never dilated; (3) paraprocts with high base and small apical process. [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

• Lindley, R.P. (1976). A new species of Ethiopian Elattoneura Cowley, 1935 from the Central African Republic, and some notes on the genus (Zygoptera: Protoneuridae). Odonatologica, 5, 153-164.
• Legrand, J. (1980). Nouvelles additions aux représentants afrotropicaux du genre Elattoneura: groupe acuta-vrijdaghi (Odonata: Protoneuridae). Revue Française d’Entomologie, 2, 153-161. [PDF file]
• Legrand, J. (1985). Elattoneura afrotropicau nouveaux ou peu connus (Odonata: Protoneuridae ). Nouvelle Revue d’Entomologie, 2, 159-168. [PDF file]
• Pinhey, E.C.G. (1961). Dragonflies (Odonata) of Central Africa. Occasional Papers Rhodes-Livingstone Museum, 1-97. [PDF file]
• Barnard, K.H. (1937). Notes on dragon-flies (Odonata) of the S. W. Cape with descriptions of the nymphs and of new species. Annals South African Museum, 32, 169-260. [PDF file]
• Pinhey, E.C.G. (1966). Notes on African Odonata, particularly type material. Revue Zoologie Botanique Africaines, 73, 283-308. [PDF file]

Citation: Dijkstra, K.-D.B (editor). African Dragonflies and Damselflies Online. http://addo.adu.org.za/ [2024-10-31].