Pine emperor moth

Pine emperor moth
Nudaurelia clarki
Nudaurelia cytherea Fabr

Larvae defoliate pine trees.

The larva moults 6 times and thus has 7 instars. The first three instars freed gregariously on pine needles. The first instar is approximately 5 mm in length and reddish brown in colour with long hairs sprouting from the tubercles on the back. The larva loses the long hairs after the second moult and subsequently have shorter spiny hairs on warty excrescences across the segments. The third instar to the seventh have opalescent disks of different colours arranged in a band pattern across the orange or maroon coloured segments that changes from blue to green to yellow to green to blue. The final instar can be up to 13 cm long and 2 cm thick (Tooke and Hubbard 1941).

The young pupa is red in colour and the colour fades to black. Pupae are 4 to 5 cm in length and can be found in the soil beneath the pine needles up to a depth of 5 cm (Tooke and Hubbard 1941).

The moths are variable in size the body can be up to 5 cm long and the wingspan can be up to 15 cm wide. The dominant wing colour ranges from bright yellow to a darker brown. There is an eye spot on each of the four wings. The size of the eye spots on the hind wings are larger than those on the forewings. The middle of the spots are transparent and four concentric coloured rings surround the eye spots, yellow, black, pink and maroon from the middle moving outward. There is variation between individuals in these coloured rings in some specimens the pink is replaced by white and in darker individuals the maroon ring blends in with the brown main colour of the wing (Tooke and Hubbard 1941).

Different strains of the pine emperor are known, and they have variation with regards to their life cycles and where they are found. For the strain feeding on pine in the Kwazulu-Natal and Mpumalanga provinces, the lifecycle can be described as follows. The pupal phase lasts up to 6 months and these can be found in the soil from June through to February. Adult moths emerge in February and fly around until May. The adult can live for up to 10 days and females lay between 150 to 200 eggs singly or in clusters of varying sizes. Females have been recorded to fly as far as 1.8 km and males 5.2 km (Van Den Berg 1974). Eggs can be found from February through to April and larvae are found from March to August. Depending on the environment the eggs last from 26 up to 84 days before hatching (Tooke and Hubbard 1941; Geertsema and Van den Berg 1973). 

The first record of the pine emperor was recorded in sketches by Sims (1903) during 1896 to 1903 (Geertsema and Van den Berg 1973).
Eastern Cape,KwaZulu-Natal,Mpumalanga,Western Cape
Africa, Southern Africa, Western Cape, Mpumalanga, KwaZulu-Natal, Swaziland (Geertsema and Van den Berg 1973)

Gallery

The adult moths in the field
Pupae
Pupae
Pupae
Larvae
Larvae
Larvae
Eggs in the field

Tooke FGC, Hubbard C(1941) the pine tree emperor moth Nadaurelia cytherea capensis, Stoll. Pretoria

Henderson HR, Warren FL, Augustyn POH, et al (1973) Isolation and structure of the sex-pheromone of the moth, Naduarelia cytherea. J Insect Physiol 19:1257-1264

Van Den Berg MA (1974) Flight activity, dispersion and longevity of adults of Naduarelia cytherea clarki Geertsema (Lepidoptera:Saturniidae). J Entomol Soc South Afr 37:67-71

Van den Berg MA (1979) Research on forest and timber insects in South Africa since 1899. Phytophylactica