Helastia plumbea


Helastia plumbea is a moth of the family Geometridae. This species is endemic to New Zealand and is found in both the North and South Islands. The species inhabits stream and river banks in montane to subalpine terrain. Adults are on the wing from October to April and are nocturnal and attracted to light. The life history of this species is, at 2024, poorly known but the larval host plants are likely mosses, herbs or possibly lichens.

Taxonomy

This species was first described by Alfred Philpott in 1915 using four specimens collected in Queenstown in November and was originally named Xanthorhoe plumbea. George Hudson discussed this species under that name in his book The Butterflies and Moths of New Zealand. Philpott illustrated the male genitalia of this species in 1928. Louis [Beethoven Prout|L. B. Prout], in 1939, discussed this species as a synonym of Xanthorhoe infantaria. In 1971 J. S. Dugdale placed this species in the genus Helastia. In 1987 R. C. Craw discussed this species while revising the genus Helastia. The male holotype is held at the New Zealand Arthropod Collection.

Description

This species was originally described by Philpott as follows:
This species can be distinguished from its sister species as a result of the blueish grey colour of the underside of the forewing as well as the reddish-ochreous discal spot on the upperside of the forewing.

Distribution

H. plumbea is endemic to New Zealand and is found in the North and South Islands. In the North Island it is recorded in the Taupo region; in the South Island it is found in the Nelson, Buller, Marlborough, North Canterbury, Westland, Mackenzie, Dunedin, Central Otago, Otago Lakes and Fiordland areas.

Habitat and hosts

This species inhabits stream and river banks in montane to subalpine terrain. Although the life history of this species is poorly known, the larval host plants of this species are likely mosses or herbs or possibly lichens.

Behaviour

Adults of this species have been observed on the wing from October to April. They are nocturnal and are attracted to light.