Ischalis fortinata
Ischalis fortinata (also known as the zigzag fern looper) is a species of moth in the family Geometridae. It was first described by Achille Guenée in 1868. This species is endemic to New Zealand. Taxonomy 
This species was first described by Achille Guenée in 1868 using a specimen collected by R. W. Fereday likely at Akaroa on the Banks Peninsula and named Polygonia fortinata. In 1875 Felder & Rogenhofer thinking they were describing a new species tentatively named it as Caustaloma ziczac. This name was synonymised by Edward Meyrick in 1883. The male holotype specimen is held at the Natural History Museum, London. Description
The mature larva of this species is a reddish-brown colour, with greenish reddish mottling, has a hairy appearance, and is between 25 and 30 mm long. Along the back of the larva there is a black edged, brown line and a number of black and white marks on a number of segments. It forms a thin cocoon on the fronds of its host plants and overwinters as a pupa. Guenée described the adults of this species as follows:

Distribution 
This species is endemic to New Zealand. It has been recorded on the North and South Islands and is abundant in native forest in the far south of the South Island. Behaviour
Eggs of I. fortinata are laid on their leaves of its host species. The adult moth is on the wing between January and March. Habitat and hosts 
This species can be found in native forest. The larval hosts of this species include Polystichum vestitum and Polystrichum richardii. The larvae feed all year round. References

Ennominae
Moths of New Zealand
Moths described in 1868
Endemic fauna of New Zealand
Taxa named by  Achille Guenée
Endemic moths of New Zealand