Nudaurelia cytherea, also called the pine tree emperor moth or Christmas caterpillar due to its festive colouration, is a southern African member of the family Saturniidae. The family has large edible caterpillars which are an important source of protein for the Bantu peoples of southern Africa. The genus Nudaurelia is closely related to Gonimbrasia and Imbrasia. The species was first described by Johan Christian Fabricius in 1775.

The larva has a most catholic taste in food plants, and readily added the needles of introduced pines to its diet, causing widespread defoliation in South African plantations in the 1930s, especially in the Lebanon and Franschhoek plantations of the Western Cape. The pines included Pinus canariensis, P. halepensis, P. radiata, P. longifolia, P. muricata and P. pinaster. Other exotic species included Acacia mollissima, Cupressus macrocarpa, Eucalyptus cladocalyx, E. diversicolor, E. globulus, E. ovata, E. paniculata, E. pilularis, Liriodendron tulipifera, apple, guava and quince. Its food plants before the introduction of exotic species had included Euclea species, Rapanea melanophloeos, Protea repens, Rhus angustifolia, Watsonia species and Myrica cordifolia - Pinus radiata and Rhus angustifolia being most sought after, with feeding migrations to other species being only incidental.

Eggs and caterpillars are sought out by a variety of hymenopteran parasitoids such as Hockeria crassa, Hockeria nudaureliae, Pediobius species, Anastatus species and Mesocomys pulchriceps, while the larvae are infected naturally by at least five distinct virus species, including Nudaurelia β virus, producing fairly regular epizootics. Insect viruses have long been valued as biological control agents, since they have few negative effects on ecosystems compared with chemical pesticides. Their most important quality is that they require no follow-up or management, while their host specificity is a great advantage over most chemical pesticides which are not. Other mammalian controlling factors are baboons, feral pigs and porcupines, all of which relish the larvae, pupae and moths. Pigs were introduced to Western Cape pine plantations by the Forestry Department in the 1930s, and proved to be a cheap and effective control measure, their acute sense of smell enabling them to easily detect pupae under the soil surface.

...