Grass Webworm moth

The Grass Webworm or Tropical Grass Webworm (Herpetogramma licarsisalis) is a moth of the Crambidae family. It is native to most of the old world tropics, including New Zealand, Hong Kong and Queensland. It is an introduced species in many other parts of the world, including Hawaii, Great Britain and the Canary Islands.

The wingspan is about 20 mm. Adults have fawn wings with rows of indistinct dark spots.

The larvae feed on various grasses of the Poaceae family and is a pest of turf and pastures in some parts of its range. They live in a tube made of the leaves of their food plant lined with silk. Young larvae are light green with a pale brown head with dark markings. Older larvae are darker with pairs of dark warts on each segment along the back. Full-grown larvae are about 20 mm long.