Pseudocoremia suavis (Forest looper moth)
Species: P. suavis
Binomial name: Pseudocoremia suavis
Common name: Common Forest Looper
Pseudocoremia suavis is a moth of the Geometridae family. It is endemic to New Zealand. It has a wingspan of about 30 mm. This moth is common throughout New Zealand at altitudes up to about 900 m, with the larvae feeding on a wide range of trees and shrubs.
This caterpillar is not known as a significant pest of native species but it has caused serious defoliation in exotic plantation forests. Several outbreaks occurred in pine plantations in Canterbury in the 1950s and early 1960s and in North Island Douglas-fir (Pseudotsuga menziesii) plantations in the 1970s. These outbreaks are the only known cases in New Zealand where large areas of exotic conifer forest were defoliated by an insect. It is thought that these outbreaks were associated with tree stress produced by drought in Canterbury and the effect of dry summers and the needle cast fungus, Phaeocryptopus gaeumannii, in Kaingaroa. Epidemic populations cause severe defoliation which leads to decreased growth rates or even to the death of badly affected trees.
For more details visit http://www.nzffa.org.nz/farm-forestry-model/the-essentials/forest-health-pests-and-diseases/Pests/Pseudocoremia-suavis/Pseudocoremia-suavisEnt11
Photos below showing the variations in wing patterns. All the moths below are males.
The underside of male moth.
Photos below are of this moths caterpillar.