Eleuthemis umbrina Dijkstra & Lempert

Dijkstra, Klaas-Douwe B., Kipping, Jens & Mézière, Nicolas, 2015, Sixty new dragonfly and damselfly species from Africa (Odonata), Odonatologica 44 (4), pp. 447-678 : 617-621

Eleuthemis umbrina Dijkstra & Lempert sp. nov. – Shadow Firebelly (Type Photo 46, Photos 59–60, Fig. 28)

Taxonomy

First recognised in Liberia as a distinctly coloured ecological form of E. buettikoferi or possibly a good species ( Lempert 1988). Genetic data show it is among the most distinct taxa within this formerly monotypic genus, particularly relative to the topotypical and sympatric E. buettikoferi ( Tree 7). The characters described for E. b. monardi Schmidt, 1951 from nearby Guinea-Bissau agree with the latter.

Material studied

Holotype ♂. RMNH.INS.501604 , Liberia, Grand Gedeh County, Putu Iron Ore Mining concession, Jebeh River at Johnsonville , sandy forested river ( Photo 60), 216 m a.s.l. (5.6329 ° N 8.1413 ° W), 10 -ii- 2011, leg. K.-D.B. Dijkstra & A. Dayeker, RMNH .

Further material. GHANA (Eastern Region): 3 ♂, Asikam Gold Mine and Wankobi stream, 291 m a.s.l. (6.2017 ° N 0.5365 ° W), 19 -vi- 2016, leg. K.-D.B. Dijkstra, RMNH . 2 ♂, Asiakwa, rocky stream SW of Asiakwa , 264 m a.s.l. (6.2533 ° N, 0.5130 ° W), 09-v- 2000, leg. K.-D.B. Dijkstra, RMNH . GHANA (Western Region): 4 ♂, bridge over Ankasa River near tourist camp , 60 m a.s.l. (5.215 ° N 2.650 ° W), 09-iv- 2000, leg. K.-D.B. Dijkstra, RMNH . GHA- NA (Volta Region): 3 ♂ 1 ♀, Agumatsa River between Wli Waterfalls and village , 261 m a.s.l. (7.1167 ° N 0.5833 ° E), 26 -iv- 2000, leg. K.-D.B. Dijkstra, RMNH . LIBERIA (Grand Gedeh County): 2 ♂ ( RMNH.INS.501603 ), as holotype, RMNH . 1 ♂, several larvae ( RMNH.INS.501503 ), Putu Iron Ore Mining concession, Sawleh river (main stream of central valley between Mts Ghi and Jideh) between Jackson’s and Biodiversity Camps , small sandy and gravelly river in somewhat disturbed rainforest, 266 m a.s.l. (5.6592 ° N 8.1979 ° W), 21 -i- 2011, leg. K.-D.B. Dijkstra & A. Dayeker, RMNH . 2 larvae ( RMNH.INS.501622 ), W of Jawordee , muddy, sandy and gravelly stream, part forested, part open with aquatic vegetation, 208 m a.s.l. (5.6167 ° N 8.3260 ° W), 12 -ii- 2011, leg K.-D.B. Dijkstra, RMNH . LIBERIA (Nimba County): 3 ♂, northern bank Yah (Dayea) River near Gbapa, Gbaleh Creek , calm sandy river in cocoa plantations, 470 m a.s.l. (7.507 ° N 8.638 ° W), 07- x- 2010, leg. K.-D.B. Dijkstra, RMNH . 1 ♂, Lugbeyee-Bonlah Road, stream on eastern side of Bonlah , large, gravelly and sandy stream in farmbush, 437 m a.s.l. (7.507 ° N 8.638 ° W), 13 -x- 2010, leg K.-D.B. Dijkstra, RMNH . 2 ♂ ( RMNH.INS.501416 ), same locality, 04-i- 2010, leg K.-D.B. Dijkstra, RMNH . LIBERIA (Grand Gedeh County): 2 ♂, Cavalla River, 33 km E of Zwedru , 206 m a.s.l. (6.083 ° N 7.83 ° W), 03–05-iii- 1982, leg. & coll. J. Lempert. 1 ♂, Dugbi River, 24 km E of Zwedru , 224 m a.s.l. (6.083 ° N 7.83 ° W), 19 -xi- 1983, leg. & coll. J. Lempert . SIERRA LEONE (Eastern Province): 1 ♂, 1 larva, Gola Forest, Gagbe stream, 1 km W of Mogbaima , parts in forest, parts in disturbed area with diamond pits, 136 m a.s.l. (7.6574 ° N 10.7788 ° W), 02-iii- 2011, leg. K.-D.B. Dijkstra, RMNH . 1 ♂, Gola Forest, Mogbai River upstream from Mogbaima , mostly gravelly and rocky river in forest, 139 m a.s.l. (7.6596 ° N 10.7676 ° W), 03-iii- 2011, leg. K.-D.B. Dijkstra, RMNH . 2 ♂ ( RMNH.INS.503110 ), Gola Forest, Wibwa (Wegbua) stream at Mayengema , 152 m a.s.l. (7.6426 ° N 10.7898 ° W), 01-iii- 2011, leg. K.-D.B. Dijkstra, RMNH .

Genetics

Four unique haplotypes (n = 6) form the sister-group of all other Eleuthemis species except E. libera sp. nov. ( Tree 7).

Male morphological diagnosis

Morphologically like E. buettikoferi with (a) moderate size, Hw 24.5 – 26.0mm (n= 3); (b) the distinct black border to labrum; (c) the vertex and occipital triangle blackened at least basally; (d) the Fw discoidal field entirely of two or more rows of cells; (e) the abdomen being entirely whitish pruinose on the upperside with maturity; (f) the largely blackish secondary genitalia; and (g) the acute tip to the hook of the hamule (like Fig. 28). However, (1) the ventral portions of the sternites of S 1–9 are yellow marked with black on the ventral carinae up to the (largely) black S 9, rather than orange with black carinae at most up to S 5, with S 9 largely orange (Photo 59). While both species vary strongly, the new species also tends to have (2)the frons darkened at the base of its central furrow, anterior to the medi- an ocellus, and not entirely pale brown; (3) more contrasting black and yellow thoracic markings with usually a black line along the humeral suture’s full length, thus not absent on its ventral section, and the black stripe on the metepimeron dead-ended dorsally, i.e., not curving forward to (almost) join the metapleural black line; and (4) the dark tips of Fw are less sharply defined and extend below Pt, rather than just touching its distal end, while Hw tips are often more darkened too.

Etymology

Latin “of shade” refers to the darker habitat and abdominal underside of the species (feminine adjective).

Range and ecology

Largely sympatric with E. buettikoferi between 100 and 500 m a.s.l. from Sierra Leone to Ghana, inhabiting shady rather than sunny sections of often the same forested streams and rivers.