Spotted Joker can change its spots

This common but attractive butterfly has a distinct seasonal variation on its underside.

Byblia ilithyia, Spotted Joker or Leliegrasvegter is a butterfly in the family Nymphalidae, the brush-footed butterflies. They are so named because, in adults, the front legs are atrophied into small brush-like sensory organs and appear to have only four legs instead of the normal six.

They are small to medium-sized orange butterflies with black bands and spots. There are two species of Jokers found in South Africa, the Spotted and Easter Joker. The Spotted Joker can be told apart from the Easter Joker by the row of black spots on the hind wing. The wingspan of the males is 38 to 43mm and the wingspan of the females 40mm to 45mm.

Spotted Joker (upperside) (Photograph: Justin Bode)

The underside of the wings can show considerable seasonal variation, with a dry season form and wet season form. This variation is, however, not as extreme as in the case of the Gaudy Commodore. Read more about the Gaudy Commodore.

Spotted Jokers have an erratic flight pattern, usually 1 to 2 metres above ground in open grassland and between bushes. They frequently settle on plants, but seldom on flowers. They are often seen sucking grass flowerheads, but nobody is yet fully sure why, as grasses do not produce nectar. Both males and females are attracted to fallen fruit.

Spotted Joker (underside) sucking on grass seeds (Photograph: Justin Bode)

The Spotted Joker is widely spread from the coast to inland savanna and grasslands from the Eastern Cape to KwaZulu-Natal, Free State, Gauteng, eSwatini, Mpumalanga, Limpopo and Northwest. They have continuous broods with a peak in November to March and a smaller peak from May to April.

The caterpillars feed on the stinging nettle creeper (Tragia durbanensis) and the wild hop (Dalechampia capensis, also known as inzula, a shrub native to South Africa, Mozambique, Eswatini, Tanzania and Zambia). The eggs are laid singly on young shoots of the larval host plant. The species is known to have large population explosions under ideal environmental conditions.