Anthene sangha, Takano, 2024

Takano, Hitoshi, 2024, Descriptions of three new species of Lycaenidae (Lepidoptera: Papilionoidea) from Parc National de Nouabalé-Ndoki, Republic of Congo with additional notes on little-known species, Zootaxa 5496 (2), pp. 214-230 : 218-220

Anthene sangha sp. nov.

( Figs 10, 13 )

Holotype ♂ ( ANHRT):

“ REPUBLIC OF CONGO 372m / Sangha Prov. , Nouabalé-Ndoki / National Park, Mbeli camp/( Gilbertiodendron forest) / 02°14’23.8”N, 16°23’52.1”E / 1–10.x.2022 MV Light Trap / Dérozier, V., Fouka, B., / Kirk-Spriggs, A., Takano, H. / ANHRT:2022.14 // ANHRTUK / 00260662”

Paratype ♂: same data as holotype (1♂ ANHRT) .

Description.

Forewing length: holotype male: 11 mm; paratype male: 10 mm.

Male. Upperside. Ground colour of head, thorax and abdomen black. Antennae black, with white scaling ventrally at the base of each segment. Ventral surface of club orange. Frons with a narrow row of white scales running adjacent to the eye. Palps longer than diameter of eye with white scaling. Abdominal segments 1–4 with white scaling along latero-posterior margin and along the entirety of the posterior margin of segments 5–8 giving the abdomen a banded appearance posteriorly. Ground colour of both wings dark brown; terminal line black; cilia greyish-brown. Forewing costa gently arcuate, rounded at apex; outer margin gently arcuate. The cell in its entirety, space 1 save for a 2 mm outer margin and the extreme base of space 2 are covered in violet-blue scales. Discal marking narrow, black. Discal and postdiscal area between veins 2–6 more sparsely covered in scales, forming a patch that differs in appearance from the rest of the wing. Hindwing arcuate, with three 1 mm long, greyish-brown ‘tails’ protruding from the outer margin along veins 1–3. The cell, spaces 1–2 and the inner margin with long light-brown ciliate scales, in the latter turning to white towards the base. The entirety of the cell, the bases of spaces 4 and 5, and the majority of spaces 1a to 3 with the exception of a 2 mm outer margin is covered in violet-blue scales. Discal marking ovoid, well-defined. The outer half of spaces 6 and 7 with sparse scaling similar to the forewing. Marginal spots, black, the one in space 2 larger than that in space 1a. Submarginal line violet-blue, well-defined, sinuate running from vein 1a to 4. Marginal line white, turning violet-blue and terminating in space 3. Underside. Head, thorax and abdomen covered in greyish-white scales. Legs black with a dusting of white scales, with a concentration of white scales at the base of each tarsal segment. Ground colour of both wings grey with indistinct and irregular discal and post-discal bands outlined in white and defined with dark brown on their inner margins but more heavily, almost forming spots, on the outer edge. Forewing submarginal and antemarginal lines white, sinuate, indistinct and interrupted at veins. Hindwing basal spot in space 7 dark brown, edged with white.

Male genitalia. Uncus robust, broadly indented medially to form two lobes. Subuncus long and fine, mediallyangled, with hooked apex. Valve elongate, without ornamentation, strongly bifurcate at its apex forming two long, sharply-pointed processes, the dorsal process slightly longer than the other. Saccus long with evenly arcuate margin. Aedeagus almost three times as long as valve, distally narrower and tapering at apex.

Female. No specimens examined (except for a photograph of a potential female—see below).

Diagnosis. Anthene sangha sp. nov. clearly belongs to the A. levis group of Libert (2010) and is reminiscent of both A. levis (Hewitson, [1878]) ( Fig. 9 ) and A. irumu ( Stempffer, 1948) ( Fig. 11 ) with which it is sympatric. It is closest to the former sharing the paler discal patch of the forewing, but the extent of the blue patch on the hindwing upperside in A. levis is much greater whilst the discoidal marking is heavily reduced. The blue colouration of A. sangha sp. nov. is however less lustrous, more akin to the markings of A. irumu . Male genitalia share similarities with both the aforementioned congeners in the elongate valve (as in A. irumu ( Fig. 14 ), although the configuration is fundamentally different) and its bifurcate apex (as in A. levis ). The genital capsule is however closest to A. levis ( Fig. 12 ) which differs from the new species in the smaller size (ca. two-thirds the size), the shallower medial emargination of the uncus, the shorter (ca. half the length) and broader (about twice the width) valves, the broader, shorter saccus and the phallus which is almost half the length. Photographs have been examined of another male specimen and a potential female from Dzanga-Sangha National Park, CAR in the collection of the late Philippe Annoyer (M. Libert, pers. comm.). This female specimen is similar in appearance to the female of A. levis sharing an all brown-upperside and a grey (rather than brown as in A. irumu ) underside but the dark brown discal markings are well-defined on both wings (like the male of the new species) and the antemarginal white band on the hindwing upperside is absent.

Remarks. The holotype and paratype of the new species were both captured on the same night at a MV light trap at Mbeli camp ( Fig. 38 ), within a small clearing in the forest. The specimens were attracted to the light during a very heavy downpour together with numerous other butterfly species belonging to various families, presumably all of the individuals having been disturbed by the strong winds and rain. Numerous other butterflies were collected at light traps throughout the time in the field, of which several were unique to this sampling technique.

Derivatio nominis. The new species is named after the Sangha River which flows through the region where the only known records of the species originate.

Distribution. The new species is so far only known with certainty from three male specimens captured in PNNN and Dzanga-Sangha National Park, CAR, and it is potentially endemic to the Sangha-Congo interfluvial zone.

Figures

FIGURES 9–14. Anthene species. Adult ♂♂ (9–11), upperside (above) and underside (below); genitalia (12–14), lateral view (left), ventral view (right) and phallus (below). 9. A. levis (Hewitson), DRC, Mbata-Siala (ANHRTUK 00330135). 10. A. sangha sp. nov., holotype. 11. A. irumu (Stempffer), ROC, PNNN (ANHRTUK 00260783). 12. A. levis. 13. A. sangha. 14. A. irumu.

FIGURES 38–40.Parc National de Nouabalé-Ndoki, Republic of Congo.38.Mbeli camp, typelocality of Falcuna nouabaleensis sp. nov. and Anthene sangha sp. nov. 39. Ndoki formation, type locality of Neurellipes smithi sp. nov. 40. F. nouabaleensis sp. nov., paratype ♂, taken in natura at Mondika camp. (All photographs V. Dérozier).