Sevenia boisduvali

The female lays a group of eggs on the undersurface of a leaf of the larval food plant. The eggs are yellowish at first, but change to brown as the larvae develop within.

A dark-patterned male pupa

An assassin bug feeding on a larva

The larval food plants in Southern Africa are Sclerocroton integerrimus (Sapium integerrimum)[2] and the jumping-seed tree[6] (Sclerocroton ellipticus). In Kenya, the larva have been recorded on Excoecaria, Phyllanthus, Macaranga, Kigelia and Sterculia.[7] The larvae are gregarious[2] and at first only eat the upper layer of the leaves, working from the tip to the base, and leaving a pale green dead leaf behind. As they grow older, the larvae begin to eat the entire leaf, starting at the leaf margin. Sometimes the larvae defoliate individual trees.[2]

The full-grown larvae attach their rear ends to a leaf or branch with a small patch of silk and hang with their heads down. After about a day or so, they shed their skin to reveal a pupa.

After shedding its skin, the pupa hardens and remains in a fairly rigid position. However the pupa can twist from side to side when disturbed. The pupae are variable in colour; being green, or creamy brown with small dark markings, or brownish and dark patterned. The pupa takes about ten days to mature and hatch into a butterfly.

Once the butterfly has emerged from the shell of its pupa, it hangs with its wings downward. The wings inflate, unfurl and dry into shape. Adult Boisduval's tree nymphs usually keep to semi-shaded areas provided by trees. They often sit head downwards on the stems or larger branches of trees, usually with the wings held closed. The adults feed on fermented fruit and on tree sap, and the males are known to land on damp patches of ground to suck up moisture.[2]