''Helastia semisignata'' is a

moth Moths are a paraphyletic group of insects that includes all members of the order Lepidoptera that are not butterflies, with moths making up the vast majority of the order. There are thought to be approximately 160,000 species of moth, many of ...

of the family

Geometridae The geometer moths are moths belonging to the family Geometridae of the insect order Lepidoptera, the moths and butterflies. Their scientific name derives from the Ancient Greek ''geo'' γεω (derivative form of or "the earth"), and ''metr ...

. This species is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found els ...

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 List of islands of New Zealand, smaller islands. It is the ...

and is only found in the

North Island The North Island, also officially named Te Ika-a-Māui, is one of the two main islands of New Zealand, separated from the larger but much less populous South Island by the Cook Strait. The island's area is , making it the world's 14th-larges ...

. The life history of this species is in need of further investigation as sources differ about what plants host the larvae. Adults are on the wing commonly from October until March.

Taxonomy

It was first described by Francis Walker in 1862 using specimens collected by A. Sinclair in

Auckland Auckland (pronounced ) ( mi, Tāmaki Makaurau) is a large metropolitan city in the North Island of New Zealand. The most populous urban area in the country and the fifth largest city in Oceania, Auckland has an urban population of about I ...

and originally named ''Larentia semisignata''. In 1877

Arthur Gardiner Butler Arthur Gardiner Butler F.L.S., F.Z.S. (27 June 1844 – 28 May 1925) was an English entomologist, arachnologist and ornithologist. He worked at the British Museum on the taxonomy of birds, insects, and spiders. Biography Arthur Gardiner ...

synonymised ''Cidaria dissociate'' and ''Cidaria semisilata'' with ''L. semisignata''. In the same publication Butler also mistakenly synonymised ''Larentia corcularia'' with ''L. semisignata''. This taxonomic error was correct by R. C. Craw in 1987. In 1912 L. B. Prout placed this species in the genus ''Xanthorhoe''. This placement was followed by

George Hudson George Hudson (probably 10 March 1800 – 14 December 1871) was an English railway financier and politician who, because he controlled a significant part of the railway network in the 1840s, became known as "The Railway King"—a title conferr ...

in his 1928 book ''The butterflies and moths of New Zealand''. Subsequently, in 1971, J. S. Dugdale placed this species in the genus ''Helastia.'' R. C. Craw confirmed this placement in his revision of the genus in 1987. The male

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of seve ...

is held at the

Natural History Museum, London The Natural History Museum in London is a museum that exhibits a vast range of specimens from various segments of natural history. It is one of three major museums on Exhibition Road in South Kensington, the others being the Science Museum ...

Description

Walker described this species as follows: Species in the genus ''Helastia'' can be difficult to distinguish from one another. However this species normally has orange scaling present on its forewings and its wing veins have black and white patches.

Distribution

This species is endemic to New Zealand. It is found in the North Island only.

Habitat

''H. semisignata'' can be found in a variety of habitats at a variety of altitudes including native forest and scrubland, subalpine herbfields and in coastal areas. This species also inhabits developed areas such as parks and gardens.

Behaviour

Adults are on the wing from most frequently from October until March and are attracted to light. They are nocturnal with adults resting on trees or stones during the day.

Host plants

LEPI Geometridae Helastia semisignata larva

Larvae of this species have been raised on mosses. But other sources state that larvae have been reared on ''

Pimelea ''Pimelea'', commonly known as rice flowers, is a genus of plants belonging to the Family (biology), family Thymelaeaceae. There are about 150 species, including 110 in Australia and thirty six in New Zealand. Description Plants in the genus ...

'' foliage or that they feed on herbs. These inconsistencies have resulted in Robert Hoare stating that further investigations into the life history of this species is needed. The adult moths have been observed visiting and likely feeding from the flowers of ''Hoheria lyallii, Olearia virgata'' and''Veronica salicifolia.''

References

{{Taxonbar, from=Q13879068 Moths of New Zealand Endemic fauna of New Zealand Moths described in 1862 Taxa named by Francis Walker (entomologist) Cidariini Endemic moths of New Zealand