Helastia clandestina


Helastia clandestina is a moth of the family Geometridae. This species is endemic to New Zealand and is found only in the South Island in and around Arthur's Pass. Adults have been collected on the wing in February and are nocturnal. Its preferred habitat is dry stony riverbeds and flood plains. The glossy blueish grey colouration of the adults of this species helps camouflage them against the rocks in their preferred habitat. H. clandestina is classified as having the conservation status of "At Risk, Relict'" by the Department of Conservation.

Taxonomy

This species was first described by Alfred Philpott in 1921 using a specimen collected by E. S. Gourlay at Arthur's Pass and named Xanthorhoe clandestina. George Hudson discussed and illustrated this species in his 1928 book The Butterflies and Moths of New Zealand under the same name. In 1987, Robin C. Craw placed this species within the genus Helastia. The holotype specimen is held at the Canterbury Museum.

Description

Philpott described the species as follows:
The glossy blueish grey colouration of the adults of this species helps camouflage them against rocks.

Distribution

This species is endemic to New Zealand. It occurs in Westland, North Canterbury and Mid Canterbury.

Biology and lifecycle

Very little is known about the biology of H. clandestina. Hudson records it being on the wing in February. Adult moths are nocturnal and are drawn to light.

Host species and habitat

The host species for the larvae of H. clandestina is unknown. H. clandestina prefers stony riverbed habitat such as at the Waimakariri River flood plain.

Conservation status

This moth is classified under the New Zealand Threat Classification system as being "At Risk, Relict".