HLEM Environmental Management: African Monarch Butterfly and Host plant Balloon Milkweed

African Monarch Butterfly Danaus chrysippus orientalis and Balloon Milkweed Gomphocarpus physocarpus

The African monarch Danaus chrysippus orientalis butterfly which is widespread in Asia, Australia and Africa belongs to the Danainae subfamily of the family Nymphalidae, is a medium-sized very attractive butterfly with a wingspan of between 7–8 cm.

Larval food plants

In Durban the larval host plants of the African monarch Danaus chrysippus are from the plant family Apocynaceae, in particular Asclepiadoideae, Gomphocarpus physocarpus, and Stapelia gigantea being two of them.

Gomphocarpus physocarpus Balloon Milkweed

Gomphocarpus physocarpus which belongs to the vast milk plant family, Apocynaceae, is one of many host plants in its range of distribution but is probably the main host plant in the Durban area for the African Monarch butterfly, which both feeds on the nectar in the flowers and lays its eggs on the plant.

The caterpillars which are immune to the poisonous alkaloids in Gomphocarpus, have developed the ability to store them and pass them on to the pupa and adult butterfly, which use them to their own advantage making them foul-tasting and poisonous to predators.

The protection strategy of Gomphocarpus has thus been effectively used by the African monarch for its own protection.

Distribution and habitat of Gomphocarpus physocarpus

Gomphocarpus physocarpus is widespread in South Africa, occurring in the Western Cape, Eastern Cape, Kwa-Zulu Natal, Mpumalanga, Gauteng, Limpopo, North West, as well as in Swaziland, Botswana, Zimbabwe and Mozambique and northwards to Kenya. It is found growing in grassland and bushveld, often along roadsides and in disturbed areas, from the coast to 900 m above sea level. Although naturalized and widespread in South Africa for some time, it is an introduced weed, native to tropical Africa.

The seeds are dispersed by wind, aided by the tuft of silky hairs attached to each seed.

Uses

Gomphocarpus physocarpus is widely used in traditional medicine in South Africa. The roots are used to treat stomachache. Leaves are dried and ground into a powder that is taken as snuff for headaches. The milky latex is used to treat warts. Seeds are blown away from the pods as a charm to placate the ancestors. The stems are used for fiber. Fresh stems and leaves stuffed into mole holes are said to be an effective deterrent. This plant is poisonous if ingested and has caused death to sheep fed large amounts.

Gomphocarpus physocarpus is an attractive quick growing yet short lived plant for the indigenous garden that attracts masses of a large variety of insects to its showy flowers that produce plenty of nectar.

The showy flowers are followed by large bladder like fruits that when mature split to release hundreds of seeds that float on the air under shiny silk parachutes.

To have masses of these very attractive butterflies in your garden all you have to do is buy a few plants from your local nursery, be given some seedlings from a friend that has them or collect and plant your own seed which germinates and grows without much attention.