Sestra flexata
Sestra flexata, also known as the common fern looper, is a species of moth in the family Geometridae. This species is endemic to New Zealand. Taxonomy
S. flexata was first described by Francis Walker in 1862 using specimens collected either in Auckland by D. Bolton. Walker originally named the species Cidaria flexata. George Hudson discussed and illustrated this species in his 1928 book The butterflies and moths of New Zealand. The male holotype is held at the Natural History Museum, London. Description
The pale yellow egg is cylindrical in shape. The larva of this species is coloured dark brown and is 25 to 30 mm long when mature. The larvae is approximately 1 to  inch long and is a brownish greenish colour with yellow tones underneath. Down its back is a brown line with two more lines down its sides. It also has a few black markings and a number of short bristles. Walker described the adult of this species as follows:

Hudson described the adults of this species as follows:

Distribution 
This species is endemic to New Zealand. This species is found throughout New Zealand including the North, South, Stewart and Chatham Islands. Host species
The larval hosts of this species are Pteris macilenta and Histiopteris incisa. It has been collected by beating the latter fern. Behaviour
The older larvae of this species feed at night. When disturbed the larva will drop to the ground. Adults of this species pollinate Leptospermum scoparium. The adult moths are nocturnal, are attracted to light and on the wing from September until March. References

Ennominae
Moths of New Zealand
Endemic fauna of New Zealand
Moths described in 1862
Taxa named by Francis Walker (entomologist)
Endemic moths of New Zealand