''Diasemia grammalis'', also known as the Arrowhead, is a moth of the family Crambidae. It is likely endemic to New Zealand and has been observed in both the North and

South Islands The Kingdom of the Isles consisted of the Isle of Man, the Hebrides and the islands of the Firth of Clyde from the 9th to the 13th centuries AD. The islands were known to the Norse as the , or "Southern Isles" as distinct from the or Nort ...

. The species inhabits open dry herb field areas. Adults are day flying and are on the wing most commonly from October until March. Larvae feed on the ground the roots of native grasses and shrubs including ''

Muehlenbeckia axillaris ''Muehlenbeckia axillaris'' (creeping wire vine, sprawling wirevine, matted lignum) is a low evergreen shrub, forming wiry mats up to about in diameter, native to New Zealand, and the Australian states of Tasmania, New South Wales and Victoria. ...

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Taxonomy

This species was first described by Edward Doubleday in the book ''Travels in New Zealand'' using a specimen collected by A. Sinclair in Auckland. The male holotype specimen is held at the Natural History Museum, London.

Description

George Hudson described this species as follows: Adults can be variable in the depth of ground colour on their wings as well as the extent of the white markings, which in some specimens can become dominant.

Distribution

This species is likely endemic to New Zealand and is found both in the North and South Islands.

Behaviour

Adults are fast flying and diurnal. They are commonly seen on the wing from October until March. Adults are also attracted to light and have been captured with light traps.

Habitat and hosts

This species inhabits open dry herb field areas from the coast up to altitudes of around 1000m. The larvae feed on the ground amongst leaflitter on the roots of native grasses and herbaceous plants including ''

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References

{{Taxonbar, from=Q5272062 Spilomelinae Moths of New Zealand Moths described in 1843 Taxa named by Edward Doubleday