Papilio antimachus, the African giant swallowtail, is a butterfly in the family Papilionidae. With a wingspan between 18 and 23 centimetres, it is the largest butterfly in Africa and among the largest butterflies in the world. The wings are long and narrow and the ground colour is orange brown with black markings. P. antimachus live in the tropical rainforests of west and central Africa. The distribution area (range) stretches from Angola, Cameroon, Democratic Republic of the Congo, Republic of the Congo, Gabon, Ghana, Ivory Coast, Liberia, Nigeria, Sierra Leone, and Uganda. It is much rarer in the west of its range than in the eastern parts of its range. It probably stays in forest canopy but males come down to mud-puddle. The male is larger than the female and can be seen in groups at nectar. The females show themselves less, continually flying high above the treetops. It has been seen hill-topping in Liberia. The butterfly may have no natural enemies because it is very toxic. The larval foodplant is unknown and nothing is published on the early stages. Cardiac glycosides found in the Imago by Miriam Rothschild indicate that the so-far unidentified larva, most probably, sequesters foodplant toxins which persist through pupation into the imago as an aposematic protection against predation, and therefore that the larval foodplant is probably an asclepiad vine.

Tropical rainforests are dense and warm rainforests with high rainfall typically found between 10 degrees north and south of the equator. They are a subset of the tropical forest biome that occurs roughly within the 28-degree latitudes. Tropical rainforests are a type of tropical moist broadleaf forest, that includes the more extensive seasonal tropical forests. True rainforests usually occur in tropical rainforest climates where there is no dry season – all months have an average precipitation of at least 60 mm. Seasonal tropical forests with tropical monsoon or savanna climates are sometimes included in the broader definition.