Eleuthemis libera Dijkstra & Kipping

Dijkstra, Klaas-Douwe B., Kipping, Jens & Mézière, Nicolas, 2015, Sixty new dragonfly and damselfly species from Africa (Odonata), Odonatologica 44 (4), pp. 447-678 : 615-617

Eleuthemis libera Dijkstra & Kipping sp. nov. – Free Firebelly (Type Photo 45, Fig. 28)

Taxonomy

The only Eleuthemis species that is well-separated from all others by its secondary genitalia, which together with its highly distinct COI haplotypes suggests it is the sister-species of all remaining species. It is potentially sympatric with congeners, being found in Angola 31 km from E. eogaster sp. nov. and in north-western Zambia 18 km from a species that morphologically is nearest to E. buettikoferi but genetically distinct; see E. eogaster ( Tree 7).

Material studied

Holotype ♂. RMNH.INS.508918 , Angola, Uíge Province, 13 km N of Negage, Lucunga river near Hinda , gravel river in open swamp and forest gallery, 1200 m a.s.l. (7.6462 ° S 15.2598 ° E), 24 -xi- 2012, leg. K.-D.B. Dijkstra, RMNH .

Further material. ANGOLA (Uíge Province): 3 ♂ ( RMNH.INS.508376 ), as holotype, RMNH . 4 larvae ( RMNH.INS.559575 , RMNH.INS.559576 , RMNH.INS.559577 , RMNH.INS.559578 ), locality as holotype, 04-x- 2013, leg. K.-D.B. Dijkstra, RMNH . ZAMBIA (Northwestern Province): 1 ♂ ( RMNH.INS.507955 ), Luakera River, 20 km N of Mwinilunga , fast flowing rocky and sandy river with several cascades in gallery forest, 1380 m a.s.l. (11.5271 ° S 24.4110 ° E), 25 -ii- 2010, leg. J. Kipping, CJKL .

Genetics Four unique haplotypes (n= 7) are the most distinct within the genus ( Tree 7). Male morphological diagnosis

Superficially similar to E. buettikoferi by the abdomen being (a) entirely whitish pruinose on the upperside with maturity; and (b) largely orange on the underside. Differs from other Eleuthemis species by (1) the pale labrum with at most a hint of a black border; (2) the pale frons darkened basally at least anteriorly to the lateral ocelli; (3) the uniformly brown occipital triangle; (4) the dark metapleural stripe expanded markedly onto the metepisternum between the metastigma and wing bases, rather than being of fairly even width throughout; (5) the Fw discoidal field with 2 to 5 single cells, rather than entirely of two or more rows of cells, although rarely up to 4 are single in others; (6) the largely pale brown rather than blackish secondary genitalia; (7) the relatively large and less divergent posterior branch of the genital lobe; and (8) the hook of the hamule with a right-angled rather than acute tip. Also notable are (9) the modest size, Hw 23.0–24.0 mm (n = 4) rather than 23.5–26.5 mm (n= 10); and (10) the dark tips of Fw that extend almost halfway along Pt, rather than just touching its distal end.

Etymology

Latin “free” refers to the separate position in the genus and its Greek equivalent eleutho used in the genus name (feminine adjective). The name Eleuthemis was presumably derived from Liberia, the nation of freed slaves, from which the type species E. buettikoferi was described.

Range and ecology

Like all Eleuthemis favours rather swift streams and rivers with overhanging trees, recorded between 1 200 and 1 400 m a.s.l. Near Negage in Angola larvae were found in an especially gravelly and fast-flowing section, while the site in north-western Zambia was also notably rapid, including waterfalls.