Gynacantha pupillata Dijkstra

Gynacantha pupillata Dijkstra   ZBK sp. nov. – Spectacled Duskhawker ( Type Photo 26, Photo 40, Fig. 15)

Taxonomy

First recorded as an unidentified female from Liberia by Lempert (1988). Recent material shows it is widespread and genetically and morphologically distinct: thus treated as a good species by Dijkstra & Clausnitzer (2014). Belongs to the bullata -group of Gynacantha Rambur, 1842 with G. bullata Karsch, 1891 , G. congolica sp. nov., G. manderica , G. nigeriensis (Gambles, 1956) , G. usambarica Sjöstedt, 1909 , and G. victoriae ( Pinhey, 1961) . Dijkstra (2005 b) synonymised the last with G. bullata on account of their (a)small size, Hw 35.0–44.0 mm; (b) pale legs with dark rings around the joints; (c) the absence of denticles in the posterior portion of the genital fossa border; and (d) the ventral carinae of S 6–8 lacking denticles. However, G. victoriae is genetically distinct ( Tree 4) and has (1) the antennal sockets on the frons usually not blackened and thus contrasting with the black vertex ( Fig. 15); (2) broad blackish smears over the humeral sutures; (3) blue markings with maturity on the plate between Hw bases, dorsally on apex of S 2 and laterally on base of S 3; and (4) shorter cerci, 5.0– 5.5 mm and less than 3 x as long as the epiproct, distinctly shorter than S 8–10 combined ( Fig. 15) [rejected synonymy].

Material studied

Holotype ♂. RMNH.INS.502124 , Congo-Kinshasa, Province Orientale, Lower Aruwimi, Bomane, Village on Aruwimi River and old oil palm plantation, 427 m a.s.l. ( 1.27 ° N 23.73 ° E), 23 -v- 2010, leg. K.- D.B. Dijkstra, RMNH GoogleMaps .

Further material. CAMEROON ( Littoral Province): 1 ♀ ( RMNH.INS.500174 ), 30 km SW of Edéa, Douala-Edéa Reserve, about 3 km east of Marienberg , narrow forest strip along a grassy swamp beside the Sanaga River, 10–20 m a.s.l. ( 3.62 ° N 9.91 ° E), 18 -vi- 2008, leg. K.- D.B. Dijkstra & K. Schütte, RMNH View Materials GoogleMaps . CONGO-BRAZZAVILLE: 1 ♀, 36 km north-east of Pointe-Noire, Hinda area , stream forest and good Hallea swamp forest, 17 m a.s.l. ( 4.5937 ° S 12.1309 ° E), 23 -vi- 2014, leg. L. Niemand & C. Ngou- lou, RMNH GoogleMaps . CONGO-KINSHASA ( Province Orientale): 4 ♂ ( RMNH.INS.502176 ), as holotype, RMNH View Materials GoogleMaps . LIBERIA ( Grand Gedeh County): 1 ♂ ( RMNH.INS.501580 ), 1 ♀ ( RMNH.INS.501581 ), Putu Iron Ore Mining concession, near former village of Boloweah , sandy and gravelly stream running from rainforest into tangly clearing, 260 m a.s.l. ( 5.6891 ° N 8.1678 ° W), 05-ii- 2011, leg. K.-D.B. Dijkstra & A. Dayeker, RMNH GoogleMaps . 1 ♀, NE of Zwedru , high forest away from water near the Cavalla River , 06-iii- 1982, leg. & coll. J. Lempert . SIERRA LEONE ( Eastern Province): 1 ♂ ( RMNH.INS.503152 ), Gola Forest, 1 km NE of Mayengema , small stream in forest, 131 m a.s.l. ( 7.6504 ° N 10.7838 ° W), 04-iii- 2011, leg. K.-D.B. Dijkstra & A. Dayeker, RMNH View Materials GoogleMaps .

Genetics

Five unique haplotypes (n= 6) are very distinct but nearest to G. usambarica ( Tree 4).

Male morphological diagnosis

Belongs to the bullata -group by (a) the distinct black mark on the frons; (b)the pale rim of the metastigma; (c) the presence of brace veins below Pt; (d) the genital fossa border with distinct rows of 8–14 denticles; (e) S 3 distinctly waisted near its base; (f) the lateral carinae of S 8 normally with denticles, like the ventral carinae; and (g) the cerci of rather even width throughout ( Fig. 15). Nearest to G. nigeriensis and G. usambarica by (h) the uniformly pale legs; and (i) the ventral carinae of S 7–8 and sometimes S 6 with denticles. However, is (1) smaller, Hw 41.0–44.0 mm (n= 7) rather than 43.0–48.0 mm (n= 33); (2) duller in colour, with an olive rather than grass green thorax, and at most the plate between Hw bases and a dorsal pair of spots on the apex of S 2 blue; (3) the frons bears an isolated black dot anterior to each antenna ( Fig. 15); (4) the wing bases have distinct dark rays to Ax 1–2; and (5) all wings have 5–14 cells doubled between R 2 and R 3 proximal to the brace vein, i.e., forming 2 cell rows. The dull colour, dotted frons and doubled cell rows are unique within the group.

Etymology

Named for the pair of pupil-like dots on the frons (feminine adjective).

Range and ecology

Rather localised but widespread in rainforest from sea level to 430 m a.s.l. in Sierra Leone, Liberia, Cameroon, Congo-Brazzaville and central Congo- Kinshasa, but precise breeding habitat unknown ( Map 7).