Byasa latreillei, the rose windmill, is a butterfly from the windmills genus (Byasa), found in various parts of Asia, comprising tailed black swallowtail butterflies with white spots and red submarginal crescents.
Hindwing: ground colour more uniform to apex of cell, beyond this interspaces 2, 3 and 4 with broad elongate white spots, the spot in interspace 2 slightly tinged outwardly with crimson; sometimes a white crimson-tinted spot also in interspace 1; a subterminal series of crimson lunules in interspaces 2 to 5, that in 5 generally more or less white; lastly, a crimson spot at apex of vein 3 and on apex of tail.
Underside similar, ground colour much paler; markings of the hindwing as on the upperside, but slightly larger, the crimson spots brighter; in many specimens a small discal adnervular spot in interspace 5, and a sub-terminal small white lunule in interspace 6 also present; the crimson-tinted discal spot in interspace 1 always present.
In India, it is found in the states of Uttarakhand, Sikkim, Assam, Meghalaya, Nagaland and Manipur.
[3] Three subspecies are described of which the following two occur in India: The specific epithet honours the French entomologist Pierre André Latreille.