Helastia cymozeucta
Helastia cymozeucta is a moth of the family Geometridae. It was first described by Edward Meyrick in 1913. This species is endemic to New Zealand and is found in both the North and the upper parts of the South Island. The adults of this species have been observed on the wing from November to January as well as in March. Taxonomy 
This species was first described by Edward Meyrick in 1913 using specimens collected by George Hudson at Ohakune and named Xanthorhoe cymozeucta. Hudson used this same name when he discussed and illustrated the species in his 1928 book The butterflies and moths of New Zealand. In 1939 Hudson, thinking he was describing a new species, also named it Xanthorhoe maoriaria. In 1971 J. S. Dugdale placed both X. cymozeucta and X. maoriaria in the genus Helastia. Craw synonymised X. maoriaria with X. cymozeucta in his revision of the genus Helastia. The male lectotype is held at the Natural History Museum, London. Description

Meyrick described this species as follows:
The genitalia of the adults of this species make it easily distinguishable from its close relative H. cryptica. However Craw stated the two are impossible to distinguish externally. The distribution of the two species can help inform identification as H. cryozeucta is found in the North Island and the upper parts of the South Island while H. cryptica is restricted to Mid Canterbury south. Distribution
This species is endemic to New Zealand. It is found in the North Island in the Auckland, Waikato, Gisborne, Taupō and Wellington regions and in the northern parts of the South Island in the Nelson, Buller and Westland regions. Habitat 
The preferred habitat of this species is native forest and scrub as well as modified habitat. H. cymozeucta can be found at altitudes ranging from lowland to subalpine. Behaviour 
The adults of this species have been observed on the wing from November to January as well as in March. References

Moths of New Zealand
Endemic fauna of New Zealand
Moths described in 1913
Taxa named by Edward Meyrick
Cidariini
Endemic moths of New Zealand