Rapala rosacea, de Nice, 1889

11. R. rosacea de Nice View in CoL ́ville, [1889] Figs 1j View FIGURE 1 , 13 View FIGURE 13

Rapala rosacea de Nicéville, [1889] : 285

Type locality: Sikkim ( India)

Common Name: Rosy Flash

Material Examined: NEPAL. Gandaki Province. Kaski. Pokhara, Phewatal , 15.iii. 1986, 795 m, leg. C.P. Smith ( ANHM, 1♂); Rupatal, 29.ii. 1992, 370 m, leg. C.P. Smith ( ANHM, 1♂) . Syangja. Putalikhet, 6.ii. 1970, 855 m, leg. C.P. Smith ( ANHM, 1♂) ( Fig. 13 View FIGURE 13 ) .

Wingspan: 38–40 mm ( Van der Poel & Smetacek 2022 for R. rectivitta )

Diagnosis ( Figs 13a, 13b View FIGURE 13 ): Rapala rosacea can be distinguished from its congeners by the narrow, often undulating dark brown postdiscal lines on its ventral wings, set against a vinous red or pink background, along with its pinkish palpi. The only other species with a similar pink background are R. rectivitta , R. nissa , and R. huangi , all of which have postdiscal lines with bronze color that are often wider. De Nicéville ([1889], p. 285) noted: “The reddish-vinous coloration of the underside at once distinguishes it from all the species of the genus known to me”.

Male Genitalia ( Figs 13c View FIGURE 13 ): Aedeagus with a short vesica, pointed to one side; valvae slender and elongated; cleft between the valvae more than half the length of the valval plate.

Biology: Not known; however, based on its seasonality, larvae potentially feed on the flowers of Rosaceae .

Natural History: Adults are typically found in forests, on flowers, particularly those of Rubus ellipticus Sm. , and along open rural trails.

Variation: Variation occurs in the postdiscal bands which can range from slightly broken to unbroken. Some individuals are potentially gray as discussed below in the remarks.

Phenology in Nepal: The rosy form flies mostly from February to mid-March after which a gray form takes over with similarly thin bands which might be R. nissa complex.

Elevation: 450– 2,200 m (personal observation)

Distribution on the Indian Subcontinent: Nepal, northeastern India ( Van Gasse 2018).

Distribution in Nepal: Kaski, Lamjung, and Lalitpur districts, but certainly more widespread across the hilly region.

Remarks: This species was recorded by Smith (1994, 2006, 2011a, 2011b) and later by Van der Poel & Smetacek (2022) as R. rectivitta . Colin Smith likely followed Evans (1932), who considered R. rosacea a form of R. rectivitta . Upon examination, all specimens previously identified as R. rectivitta in the studied Nepalese collections ( ANHM and SNHM) were found to represent either R. nissa , R. huangi , or R. rosacea . All authors of this study have recorded R. rosacea in Nepal: SKC from Kaski (Pokhara), Lamjung (Bhorletar), and Lalitpur (Godavari) districts; PvdP from Kaski (Pokhara) District; SP and AS from Kaski (Pokhara) District; and MSL from Lalitpur (Godavari) District. Notably, the rosy, reddish-vinous-colored R. rosacea occurs mostly from February to mid-March in Nepal, after which only grayer individuals are observed. This suggests that R. rosacea is an early spring univoltine butterfly in Nepal, emerging from February to mid-March after which only R. nissa complex, including R. rectivitta , flies. However, Inayoshi (2024) suggests that the phenology of R. rosacea extends until December in Thailand and Vietnam. Further research is needed on the phenology and possible morphological variation of this taxon.