Neurellipes smithi, 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 : 220-223

Neurellipes smithi sp. nov.

( Figs 19–22 , 26 )

Holotype ♂ ( ANHRT):

“ REPUBLIC OF CONGO 352m / Sangha Prov., Nouabalé-Ndoki / National Park, Ndoki formation / (secondary forest) / 02°12’47.7”N, 16°23’45.8”E / 29.ix–01.x.2022 General Coll. / Dérozier, V., Fouka, B., / Kirk-Spriggs, A., Takano, H. / ANHRT:2022.14 // ANHRTUK / 00260669”

Paratypes (13♂♂ 2♀♀):

REPUBLIC OF CONGO: same data as holotype (2♂♂ ANHRT) ; Mbeli camp, Nouabalé-Ndoki National Park, 372m, 02°14’23.8”N, 16°23’52.1”E, 1–10.x.2022, leg. V. Dérozier, B. Fouka, A. Kirk-Spriggs & H. Takano (2♂♂ ANHRT) ; Bomassa camp, Nouabalé-Ndoki National Park, 341m, 02°12’36.9”N, 16°11’30.2”E, 06–14. v.2023, leg. V. Dérozier, A. Kirk-Spriggs, G. László & S. Mvouende (3♂♂ 2♀♀ ANHRT) ; Bomassa Forest , Nouabalé-Ndoki National Park, 358m, 02°11’58.1”N, 16°11’58.1”E, 17–21.x.2022, Malaise trap, leg. V. Dérozier, B. Fouka, A. Kirk-Spriggs & H. Takano (4♂♂ ANHRT) ; same data but 17–23.x.2022, general collection (1♂ ANHRT) ; Mombongo camp, Nouabalé-Ndoki National Park, 352m, 02°10’30.7”N, 16°08’37.7”E, 02–06.ii.2023, Malaise trap, leg. N. Bakala, V. Dérozier, A. Kirk-Spriggs & G. László (1♂ ANHRT) .

Description.

Forewing length: holotype male: 13 mm; paratype males: 11–16 mm; paratype females: 14–15 mm.

Male. Upperside: ground colour of head, thorax and abdomen black.Antennae black, with white scaling ventrally at the base of each segment. Frons with a narrow row of white scales running adjacent to the eye. Palps longer than diameter of eye with white scaling. Abdominal segments with dark greyish-brown scaling along posterior margin of segments giving the abdomen a slightly banded appearance. Ground colour of both wings dark brown; terminal line black; cilia greyish-brown. Forewing costa gently arcuate, rounded at apex; outer margin gently arcuate. Discal marking ovoid, longitudinally elongate, pale-orange in colour, occupying the dorsal half of space 1 and distally to within 3 mm of the outer margin, space 2 in its entirety except for a 2 mm outer margin, and the base of space 3. Hindwing arcuate, with three 1 mm long, greyish-brown ‘tails’ protruding from the outer margin along veins 1a, 2 and 3. Ground colour slightly paler dorsally, from space 7 to 8. The cell, spaces 1–2 and the inner margin with long light-brown ciliate scales. Discal marking pale orange, in the form of a submarginal band running broadly parallel with the marginal band from the dorsal half of space 1a to the ventral half of space 4. Marginal band formed of black spots boldly surrounded proximally and laterally with pale orange and a thin white fascia parallel to the outer margin distally; spots in space 1 conjoined, the proximal margin strongly emarginate medially. Both discal and marginal bands strongly bisected with heavy black scaling along the veins. Underside. Head and thorax covered in greyish-white scales. Legs dark brown with a dusting of white scales, with a concentration of white scales at the base of each tarsal segment. Abdomen with dense cream ciliate scales. Ground colour of both wings pale brownish-grey with white bilineate bands and fasciae; discal triangle with pale-orange marking from upperside weakly showing through; terminal line dark brown. Forewing basal band with two lines converging dorsally, filled with darker brown scales and in space 1 deep charcoal. Discal band defined with dark brown on the inner edges. Postdiscal band indented, defined with dark brown forming spots on its inner edge. Antemarginal and Submarginal lines indistinct, broadening towards ventral margin; the space in between filled with dark brown scaling from space 3 to ventral margin. Marginal line fine, indistinct and interrupted at veins. Hindwing with basal and discal bands irrorated internally with darker scales. Postmedial band indented, defined with dark brown forming spots on its inner edge. Antemarginal fascia arcuate, diffuse. Marginal fascia mirroring upperside, but the black spots replaced with the ground colour and the orange replaced with white except for in spaces 1 and 2; these two spots with a ring of iridescent green scaling.

Male genitalia. Uncus robust, indented with a broad concavity medially. Subuncus long and fine, almost rightangled medially with hooked apices. Valve rectangular, the distal margin finely serrate with two sharp projections ventro-distally, the ventral projection longer than the dorsal one. Saccus long, its margins evenly arcuate in ventral view. Aedeagus almost three times as long as valve, distally narrower and tapered at apex.

Female. Similar to male but paler and fringe longer. Outer margin of forewing more arcuate. Hindwing upperside marginal band extending to space 6 becoming paler and more indistinct towards the costa.

Diagnosis. The new species is very similar in appearance to the sympatric Neurellipes ngoko ngoko ( Stempffer, 1962) ( Figs 15–18 ), but in both sexes of the latter, the upperside markings are a darker reddish-orange, and the hindwing discal marking is larger often extending into space 5 and reaching the cell in spaces 2 and 3 combined with limited fine black scaling along the veins giving the appearance of a continuous patch. The underside ground colour of N. ngoko is a darker brownish-grey, and the dark brown spots in the postdiscal bands are much better defined. Markings are however variable in both species and the development of the upperside orange markings can be heavily reduced ( Figs 15, 19 ) or strongly expressed ( Figs 17, 21 ). In the male genitalia, the general configuration is very similar but in N. ngoko ( Fig. 25 ), the capsule is larger, the ventro-distal projections of the valve are nearly twice as long, and the concavity between them is broader. Although the upperside markings and colouration are different, N. rufomarginata ( Bethune-Baker, 1910) ( Fig. 24 ) shares a similar genital ground plan but differs in the shorter valves, finer ventro-distal projections of the valve and a narrower concavity between them ( Fig. 27 ). Intraspecific PWDs of the new species were 0.0–0.2% (n=5) and diverged interspecifically from N. ngoko by 2.5–3.5% (n=6).

Remarks. A long series of Neurellipes specimens with the elongate orange oval marking on the forewing was captured, in part due to the deployment of Malaise traps in suitable habitats (Takano et al. 2024). Malaise traps accounted for 32 of the 54 specimens of N. ngoko , and five of the 16 specimens of N. smithi sp. nov. collected at PNNN. Neurellipes ngoko was described from Ouesso, ROC and is not known from anywhere east of the Congo River ( Libert 2010), whilst its allopatric sibling N. rufomarginata , distributed in north-eastern DRC, is separated by some 800 km (its most westerly record being Kisangani). There is however a short series of specimens (n=11) from Kwokoro, DRC ( Fig. 23 ) in the ANHRT collections somewhat intermediate between N. ngoko and a N. rufomarginata specimen from Epulu, DRC figured on Plate XXIV of Libert’s (2010) revision. Although the genitalia and the deeper orange colouration of the wing markings are similar to true N. ngoko , the wing patterns are consistently more reduced and less well-defined; this population may yet constitute an undescribed taxon but without barcode data, its identity is not dealt with any further herein and merely highlighted as being a group that requires further investigations. The male specimens of N. ngoko from PNNN also show a high degree of variability with some males ( Fig. 17 ) displaying phenotypes very similar to N. ngoko fontainei Libert, 2010 from Sankuru, DRC. Based on the series collected at PNNN, it is possible that ssp. fontainei is merely a form of nominotypical N. ngoko , but since the distribution is disjunct (ca. 800 km apart), the two taxa are maintained as being separate for the time being until further material becomes available in between these populations.

Derivatio nominis. It is with great pleasure that I dedicate this new species to Richard Smith, Chairman of the Board of Trustees, ANHRT, for his outstanding and ongoing contribution to African entomology and biogeography through the institution he founded.

Distribution. The new species is known only from PNNN but may be more widely distributed in the Sangha-Congo interfluvial region.

Figures

FIGURES 15–24. Neurellipes species. Adults, upperside (above) and underside (below). 15. N. ngoko ngoko (Stempffer), ♂, ROC, PNNN (ANHRTUK 00321840). 16. Id. (ANHRTUK 00260807). 17. Id. (ANHRTUK 00260771). 18. Id., ♀, ROC, PNNN (ANHRTUK 00260682). 19. N. smithi sp. nov., paratype ♂ (ANHRTUK 00289864). 20. Id., holotype ♂. 21. Id., paratype ♂ (ANHRTUK 00260696). 22. Id., paratype ♀ (ANHRTUK 00321906). 23. N. cf. ngoko, ♂, DRC, Kwokoro (ANHRTUK 00289939). 24. N. rufomarginata (Bethune-Baker), ♂, DRC, Mamove (ANHRTUK 00363939).

FIGURES 25–27. Neurellipes species ♂ genitalia. Capsule in lateral view (top), phallus (middle) and valve in three-quarter view (bottom). 25. N. ngoko ngoko (Stempffer), ROC, PNNN (ANHRTUK 00260768). 26. N. smithi sp. nov., holotype. 27. N. rufomarginata (Bethune-Baker), DRC, Mamove (ANHRTUK 00363939).