Neolycaena (Rhymnaria) arcana, Weidenhoffer & Šumpich, 2017

Weidenhoffer, Zdeněk & Šumpich, Jan, 2017, Neolycaena (Rhymnaria) arcana sp. nov. from Tibet (Lepidoptera: Lycaenidae), Acta Entomologica Musei Nationalis Pragae 57 (1), pp. 275-278 : 276-278

Neolycaena (Rhymnaria) arcana sp. nov.

( Figs 1–7 )

Type locality. Tibet (in its wider, pre-1950 concept).

Type material. HOLOTYPE: J, ‘ Tibet. [handwritten]’, ‘HolotypusJ / Neolycaena (Rhymnaria) / arcana / Weidenhoffer & Šumpich, 2017 [red label]’ ( NMPC).

Description. Adult ( Figs 1–2 ). Forewing length (from apex to point of attachment to thorax) 14.6 mm, length/width ratio 1: 0.6. Ground colour of upperside of wings brown, slightly paler in basal and apical part of forewing and anal part of hindwing. Weakly visible dark brown row of spots in submarginal part of hindwings. Narrow marginal line of both wings blackish brown, fringes brown. Underside of forewing dark brown, lighter in costal and marginal part of wings; narrow marginal line and fringes dark brown, white antemarginal line absent, submarginal dark spots indistinctive. White postdiscal band not reaching inner margin but well developed and formed by row of crescent spots. Wing drawings completed by thin white line at discocellular vein. Underside of hindwing in basal and discal parts light brown, in postdiscal part even paler. Marginal line and fringes dark brown, white antemarginal line weakly developed. Submarginal row formed by twofold row of rounded black spots joined with inconspicuous yellow link; inner spots of twofold row markedly larger than outer spots. White postdiscal band very prominent and formed by wide crescent spots bordered by blackish brown crescents from inner side. Regular bow of postdiscal spot interrupted only in field 6; this spot markedly shifted to base of wing. Discocellular vein white-bordered. Antennal club ventrally black with ochreous tip, dorsally fully ochreous-coloured.

Male genitalia ( Figs 4–7 ). In ventral projection valvae distally terminated by short transparent spine, basal part of valvae equal to three fifth of total length, narrowing distally. Saccus well developed, laterally curved. Falces long, arcuately saggy, distally narrowed till spear shaped ending. Saccus well developed, in lateral projection curved. Aedeagus with two long cornuti and sclerotized keel.

Female genitalia. Unknown.

Differential diagnosis. Only two species ( N. (R.) aeto Zhdanko, 1994 and N. (R.) arcana sp. nov.) from the whole subgenus Rhymnaria have a white row of postdiscal spots in the shape of broad crescents on the underside of hindwings. All other species of the subgenus have postdiscal spots in the form of white lines or white dots. From N. (R.) aeto the new species differs in having dark brown crescents proximally adjacent to the white ones; in twofold submarginal row of black spots with the internal spots always significantly larger than the external ones (same size by N. (R.) aeto ); in the length of forewing (17–18 mm at N. (R.) aeto ). The morphology of the male genitalia, especially the apical part of valvae (either rounded or sharply pointed) has a diagnostic relevance at a species level as well. Neolycaena (R.) arcana sp. nov. together with seven other species ( N. (R.) aeto , N. (R.) davidi , N. (R.) falkovitschi Zhdanko & Korshunov, 1985 , N. (R.) oschi Zhdanko, 1998 , N. (R.) rhymnus , N. (R.) tangutica , and N. (R.) zhdankoi Churkin, 2006 ) belongs to a species group with spined valvae.

Etymology. The species epithet is the Latin adjective arcanus (- a, - um), meaning mysterious, hidden.

Biology. Unknown.

Distribution. Tibet (in its wide pre-1950 extent) (this paper).

Remark. Unfortunatelly, due to the ageing process the specimen suffered certain change in colouration and therefore it is not possible to establish the exact original tint of the brown colour.

Figures

Figs 1–7. Neolycaena (Rhymnaria) arcana sp. nov.1–2 – male (holotype):1 – dorsal view; 2 – ventral view;3 – original label; 4–7 – male genitalia: 4 – ventral view; 5 – lateral view; 6 – detail of spine in distal part of valvae; 7 – aedeagus.