Rhagastis confusa Rothschild & Jordan, 1903, Novit. zool. 9 (suppl.): 793 (key), 795. Type locality: [India, Meghalaya,] Khasia Hills [Khasi Hills].
Synonym. Rhagastis confusa chinensis Clark, 1936.
Synonym. Rhagastis confusa peeti Clark, 1936.
Wingspan: 84--90mm. Wings broader than in Rhagastis castor aurifera. Forewing as in Rhagastis castor aurifera, but darker in tint, costal margin pale; fringe of hind margin white in middle, continuous with the pinkish-white, longitudinal -- subbasal line indicated in Rhagastis castor aurifera and other species. Hindwing pale band more pinkish and broader than in Rhagastis castor aurifera. Forewing anterior half of cell reddish, not brownish-black, of the same colour as the disc; the brown discal band just outside the basal area absent or only vestigial at costal margin of fore- and hindwing; the discal dots as large as in Rhagastis castor aurifera; marginal band of forewing and the stripe connecting it with basal area less prominent than in Rhagastis castor aurifera. Head and thorax brown with a sharply defined whitish-pink lateral band, which is shaded with brown near base of forewing. Metanotum with indistinct black mesial dot. No tawny-ochreous subdorsal stripe on abdomen. Middle of sterna and abdomen buff-pink on underside, dusted with a few black scales. Labial palp segment 1 apical cavity distinct; segment 2 broadest at base, longer than broad, as in Rhagastis castor aurifera. Outer row of forebasitarsal spines double only at base (Bell & Scott, 1937).
In the male genitalia, aedeagus similar to Rhagastis castor aurifera but more asymmetrical, the right process broader and with teeth along the proximal and apical edges.
Similar in general appearance and size to Rhagastis albomarginatus albomarginatus, but immediately distinguishable by the almost uniform olive-green ground colour of the forewing upperside and the lack of a small black discal spot on the hindwing underside.
China: iv (Guizhou); v (Yunnan); vii (Yunnan); viii (Sichuan).
LARVA: Full-fed 90mm, width 11mm, horn 7 mm. According to Bell & Scott (1937), in the final instar very similar to that of Rhagastis castor aurifera; horn tapering evenly to a point, sides not flattened. Surface as in Rhagastis castor aurifera.
In colour, head and segments 2 to 5 green with a yellowish tinge on dorsum, rest of body very pale bluish, nearly white. A narrow green dorsal stripe runs from 2 to base of horn. A broader white dorso-lateral stripe is also present from 3 to base of horn, broken by the eye-spot on 5, and on 6 to 10 broken before the hind margin of each segment. This is curved convexedly dorsad and edged above with green, from 11 running straight across 12 to base of horn. Eye-spot on 5 longitudinally elongate-oval, pupil elongate-oval, deep blue in front, sap-green behind, the green part bearing two or three large white dots placed longitudinally; the pupil edged broadly above, less broadly elsewhere, with white, the whole edged narrowly with sap-green; front edge of eye-spot encroaching on to 4. There are broad, pale blue oblique lateral stripes on 6 to 10, these running into the dorso-lateral stripe above. Horn purple; legs pink. Spiracles whitish with a brown patch, on each side of the central slit, and a narrow dark green rim (Bell & Scott, 1937).
PUPA: 50mm, width 10mm, and very similar to Rhagastis castor aurifera. Colour of head, thorax and wing-case dark brown speckled and streaked with black, especially on dorsum; abdomen pale brown dorsally and ventrally, sides black with large, irregular, white patches round the spiracles; wing-case separated from abdomen by a conspicuous white line from base to near tip; bevels of free abdominal segments pink (Bell & Scott, 1937).
Tongue-case projecting considerably in front of head, semi-circular in side-view; head with frons sloping steeply downwards, and between it and upper edge of base of tongue-case there is a sharp transverse dorsal ridge. From the lower edge of the tongue-case the ventral surface is concave to the middle of wing-case, then convex to the tip of wing-case, the curves being more strongly developed than in others of the genus. Surface dull, tongue-sheath coarsely rugose, veins of wings and legs prominent and set with tubercles; rest of body smooth. Spiracles white with a broad black band across the middle. Cremaster triangular, upper surface rugose underside deeply hollowed, ending in two cylindrical shafts, each of which branches into two spines; two or three double-pointed spines on lateral edge of cremaster near tip (Bell & Scott, 1937).
The pupa when handled moves the abdominal segments freely.
Larval hostplants. Vitis in India (Bell & Scott, 1937).
China: Sichuan (Kangding; Baoxing; Dadu He; Qiaoqi); Yunnan (Changning Co., Songzhishanding, 2800m; Gaoligong Shan; Huaping Co., Dabaoshan); Guizhou (Jiucai Ling).
Northern Pakistan, northern India (Bhuyan, Clark & Smetacek, 2019; Jatishwor Irungbam & Fric, 2021), Nepal, Bhutan, northern Thailand, southwestern China and northern Vietnam (Sa Pa, Lao Cai Province).