About Cyrestis lutea Zincken, 1831
Like other white species in the genus Cyrestis, Cyrestis lutea has very fine, evenly spaced meridional stripes. On its hindwing, the submarginal band lacks a blue decorative line, but holds two distinct chain-pattern links at its anal end. The yellow markings at the anal angle of both wings are quite distinct, but not highly noticeable against the wing’s ground colour. The most prominent characteristic of this species is the unusual colouration of the female: females are white, a trait not seen in any other Cyrestis species. White female Cyrestis lutea are very rare; over many years, collector Fruhstorfer captured only 2 to 3 specimens. These white females differ from male and female Cyrestis nivea in their less pure white wing colour, increased transparency of the forewing’s apical region, which is light grey rather than brown-black, and the way the white ground colour reaches the forewing’s costal margin between the third (outer) meridional stripe and the submarginal band. Their markings match those of male Cyrestis lutea in two key features: the position of dark blue spots on the anal projections, and the middle line of the hindwing’s submarginal band being broken into a small number of streaks.
