12. R. dieneces dieneces (Hewitson, 1878) Figs 1l, 14

Deudorix dieneces Hewitson, 1878: 31

Type locality: Singapore

Common Name: Scarlet Flash

Material Examined: INDONESIA. Sumatra. Aceh Province. Simeulue, xi.1992, MGCL 1201843, Genitalic Vial KW-24-98 (MGCL, 1♂) (Fig. 14a); same data, MGCL 1206505, Genitalic Vial KW-24-116 (MGCL, 1♂). North Sumatra Province. Utara, Prapat, 9.vi.1963, leg. Dr. Diehel, MGCL 1201844, Genitalic Vial KW-24-111 (MGCL, 1♀) (Fig. 14b) .

Wingspan: 30–36 mm (Van der Poel & Smetacek 2022).

Diagnosis (Figs 14a, 14b): Rapala dieneces dieneces can be distinguished from similar congeners with red dorsal wings occurring in Nepal by its red coloration, which is typically confined to the areas below and beside the cell on both the dorsal fore- and hindwing. The male differs from the similar-looking R. damona primarily by its more confined red coloration on the dorsal hindwing that does not extend into space 7. Ventrally, R. dieneces dieneces can be distinguished from R. damona by the tornal patch of blue speckles in hindwing space 1c which is far away from the band, prominent orange crown above the black tornal spot in space 2, and forewing postdiscal band, which is mostly straight. Male is red above, while female is brown.

Male Genitalia (Figs 14c–14e): Aedeagus vesica with two hook-shaped tips projected upward in the same fashion as in R. pheretima (cf. one hook only), one much larger than the other; valvae elongated and sinuate with narrowed apices; cleft between the valvae more than half the length of the valval plate.

Female Genitalia (Fig. 14f): Anterior apophysis short; ductus bursae very slender and elongated with distal end lacking a distinct head; corpus bursae round and bulbous with a thick center, a short signum on either side near the apex with a single large hook-shaped spine inside.

Biology: The larvae are known to feed on the flowers of Durio zibethinus Murray, Syzygium grande (Wight) N.P. Balakr., Nephelium lappaceum L. (Ek-Amnuay 2012), and Allophylus triphyllus (Burm.fil.) Merr. (Wynter-Blyth 1957).

Natural History: Adults are typically found in sparse forests (Van der Poel & Smetacek 2022).

Variation: The postdiscal bands on ventral forewing range from straight to angulated in the middle. The brightness of the orange crown on the black tornal spot on the ventral hindwing may also vary.

Phenology in Nepal: August (Smith 1994).

Elevation: 180 m (Smith 1994).

Distribution on the Indian Subcontinent: Northeastern India, Bangladesh, and westward to the eastern Terai of Nepal (Van Gasse 2018).

Geographic Distribution: Jhapa District (Van der Poel & Smetacek 2022), potentially in Bandipur, Tanahun District (Fig. 1l).

Remarks: In Nepal, R. dieneces has been recorded only once, in August 1974, from Jhapa District (Smith 1994; Van der Poel & Smetacek 2022). A tentative record by the first author from Bandipur, Tanahun District, on June 8, 2019, at 1,040 m (Fig. 1l) remains unverified due to the absence of dorsal images.