Mesene leucogyna notia Hall & Lamas

Hall, Jason P. W. & Lamas, Gerardo, 2007, Four new symmachiine taxa from the eastern Andes of Peru and Ecuador (Lepidoptera: Riodinidae), Zootaxa 1533, pp. 41-52 : 46-47

Mesene leucogyna notia Hall & Lamas , new subspecies

(Figs. 2A,B; 6; 10)

Description: MALE: Forewing length 12 mm. Forewing costa approximately straight, distal margin very slightly convex, four forewing radial veins; hindwing round. Dorsal surface: Ground color of both wings orange; forewing with evenly narrow black border along distal margin and very narrow black border along costal margin tapering towards wing base; hindwing with evenly very narrow black border at distal wing margin extending from apex to tornus; fringe on both wings entirely black. Ventral surface: Forewing same as dorsal surface, but orange slightly paler and black wing borders slightly broader; hindwing same as dorsal surface, but orange slightly paler, distal black border slightly broader, an evenly very narrow black border present along anal margin, and an evenly narrow black band present below costal margin, leaving a narrow pale orange area along basal two-thirds of costal wing margin itself.

Head: Labial palpi a mixture of dark brown and cream scaling, second and third segments short; eyes brown and bare, lateral scaling dark brown; frons dark brown, with cream scaling laterally and ventrally; antennae approximately 70% of forewing length, antennal segments black with a discontinuous nudum section lateroventrally, clubs black.

Body: Dorsal surface of thorax predominantly dark orange, ventral surface predominantly black; dorsal surface of abdomen dark orange, lateral margins dark brown, ventral surface a mixture of black and grayish scales; a broad and continuous band of concealed androconial scales present dorsally across posterior margin of abdominal tergites four, five and six; forelegs cream, mid- and hindlegs a mixture of brown and cream scales.

Genitalia ( Fig. 6 ): Same as those of nominotypical M. leucogyna , but both upper and lower sections of valvae slightly more posteriorly elongate, with a consequently slightly deeper medial indentation.

Female: Forewing length 13 mm. Forewing costal margin approximately straight, distal margin convex; hindwing round. Dorsal surface: Ground color of both wings white; costal margin and distal half of forewing black, distal third of hindwing black, with black extending in a broad band below costal margin from apex to wing base, leaving a very narrow white strip along basal two-thirds of costal margin, distal margin of basal white areas on both wings rounded; fringe on both wings entirely black. Ventral surface: Same as dorsal surface.

Head: Same as male, but nudum on antennal segments continuous.

Body: Dorsal and ventral surfaces of thorax black with some white scaling; dorsal and lateral surfaces of abdomen black, ventral surface a mixture of black and white scaling; no abdominal androconia present; all legs predominantly dark brown.

Genitalia ( Fig. 10 ): Same as those of nominotypical M. leucogyna , but ostium bursae ill-defined ventrally, and posterior section of ductus bursae more lightly sclerotized.

Type material: Holotype ɗ, PERU: Cuzco, San Pedro, 1400 m, “ 13°09’S 71°26’W ” [inaccurate], 31 Aug 1989 (R. K. Robbins) (National Museum of Natural History, Smithsonian Institution, Washington, DC, USA [USNM]).

Paratypes: PERU: Cuzco, 1Ψ: San Pedro, 1400 m, 13°03’S 71°33’W, 15 Aug 2001 (J. Grados) (MUSM).

Etymology: The name of this taxon has been derived from the Greek and Latin words for “southern”, in reference to its southerly distribution within the Andes.

Diagnosis: Given that this new taxon and Mesene leucogyna have non-overlapping ranges, the same habitat preferences, similar wing patterns and virtually identical genitalia, we tentatively describe notia as a subspecies of M. leucogyna rather than as a distinct species. However, additional material is clearly needed before the taxonomic status of notia can be definitively determined. The male of M. leucogyna notia differs from that of nominotypical M. leucogyna by having brighter orange dorsal coloration, a narrower black border around the dorsal forewing apex, no narrow black border along the costal and anal margin of the dorsal hindwing, uniform orange ventral coloration instead of cream coloring that fades to gray at the base of the hindwing, narrower black instead of brown borders around both ventral wings, and cream instead of whitish scaling on the ventral areas of the head, thorax and abdomen. Slight differences in size and the degree of convexity of the distal forewing margin are probably not significant. The male genitalia of M. leucogyna notia , at least those of the single example examined, differ very slightly in the shape of the valvae, which have slightly more posteriorly elongate upper and lower sections, with a deeper medial indentation between them. The female of M. leucogyna notia differs from the illustrated putative female of M. leucogyna leucogyna , which may actually belong to a separate subspecies, by having a subcostal black band on the ventral hindwing. The single examples of female genitalia examined for the two taxa differ slightly in the degree of sclerotization along the ventral margin of the ostium bursae and across the broad posterior section of the ductus bursae, with M. leucogyna notia lacking a well sclerotized ventral margin to the ostium and having a hardened membranous posterior section to the ductus bursae rather than a well sclerotized one, but such differences may well not be diagnostic.

Biology: Nothing is known about the biology of this very rare taxon, except that it inhabits wet montane forest at about 1400 m.

Distribution: Mesene leucogyna notia is currently known only from the southern Peruvian department of Cuzco, but its range will undoubtedly eventually be found to include the Andes of Bolivia.

Figures

FIGURES 5 – 8. Symmachiini male genitalia in lateral view. 5. Mesene leucogyna leucogyna, holotype %, Qbda. Siete Jeringas, Junín, C. Peru (MUSM). 6. Mesene leucogyna notia, holotype %, San Pedro, Cuzco, S. Peru (USNM). 7. Mesene margaretta anartia, paratype %, Pakitza, Madre de Dios, S. Peru (MUSM). 8. Symmachia pena, holotype %, Qbda. Siete Jeringas, Junín, C. Peru (MUSM). Scale bar = 1 mm.

FIGURES 9 – 10. Symmachiini female genitalia in dorsal view. 9. Mesene leucogyna leucogyna, putative Ψ, Yakunk- Cutucú trail, Morona-Santiago, S. Ecuador (JHKW). 10. Mesene leucogyna notia, paratype Ψ, San Pedro, Cuzco, S. Peru (MUSM). Scale bar = 1 mm.