Pseudagrion pacale Dijkstra

Dijkstra, Klaas-Douwe B., Kipping, Jens & Mézière, Nicolas, 2015, Sixty new dragonfly and damselfly species from Africa (Odonata), Odonatologica 44 (4), pp. 447-678 : 530-532

Pseudagrion pacale Dijkstra sp. nov. – Peace Sprite (Type Photo 21, Photos 32, 75, Fig. 12)

Taxonomy

Belongs to a subgroup of Pseudagrion B-group species that favour larger and swifter flowing waters. These include P. acaciae Förster, 1906 , P. sublacteum (Karsch, 1893) , P. vaalense Chutter, 1962 and probably P.niloticum Dumont, 1978 . Present species is morphologically and genetically clearly differentiated.

Material studied

Holotype ♂. RMNH.INS.501668 , Sierra Leone, Eastern Province, 7 km S of Kenema, Moa River at Tilorma , large river with gallery forest and rocky rapids ( Photo 32), 147 m a.s.l. (7.8123 ° N 11.1779 ° W), 26 -ii- 2011, leg. K.- D.B. Dijkstra, RMNH .

Further material. 2 ♂ ( RMNH.INS.501661 , RMNH.INS.501670), 1 ♀ ( RMNH.INS.501669 ), as holotype, RMNH . 3 ♂ ( RMNH.INS.501674 ), 1 ♀, same locality, 15 -iii- 2011, leg. K.-D.B. Dijkstra, RMNH .

Genetics

Two unique haplotypes (n = 5) distant from but nearest to P. sublacteum ; more distant to P. acaciae and P. vaalense ; P. niloticum not sampled.

Male morphological diagnosis

Nearest to P. sublacteum by (a) the essentially similar markings including reddish eyes, face and ante-humeral stripes; (b) the broad lateral and apical lobes of the penis; (c) the narrow and slender cerci that clearly surpass the paraprocts; and (d) the hatchet-shaped paraprocts, with a prominent dorsal knob in lateral view ( Fig. 12). However, (1) is larger, Hw 21.5 –24.0mm (n = 6) rather than 18.5 –21.0 mm (n = 6); (2) the postocular spots and antehumeral stripes become deep orange and the thorax sides pale green with maturity, rather than all turning dark and eventually uniformly pruinose; (3) the postocular spots are clearly framed with black; (4) the apical cleft of the penis is deep and narrow, while its wide lateral lobes bear tiny projections, thus the penis most recalls that of P. coeleste Longfield, 1947 ; (5)the paraprocts are pointed rather than rounded in dorsal view; and (6) the dorsal knob of the paraprocts is much higher than deep and thus more pronounced than in other African Pseudagrion species ( Fig. 12).

Etymology

Latin “belonging to peace” to contrast with the 1991–2002 civil war in which the Moa River was a frontline and the Ebola epidemic since 2013 of which the Kenema region was the national epicentre (neuter adjective).

Range and ecology

Rocky sections with rapid flow of the broad Moa River between 120 and 150m a.s.l. in Sierra Leone; also seen at Tiwai Island, 35 km downstream of the type locality.