Cotton Web Spinner

Achyra affinitalis · Order: Lepidoptera · Family: Crambidae

Damages trees, gardens or crops. Its larvae damage crops such as cotton, sorghum, alfalfa, sunflower and related plants.

Source: Wikipedia

Cotton Web Spinner
Photo: Donald Hobern, CC BY

The cotton web spinner is a moth in the family Crambidae with a wingspan of about 20 mm. It occurs in Australia and New Zealand. Its larvae feed on several crops, including cotton, sorghum, alfalfa, sunflower and related plants, making it a garden and farm pest.

Source: Wikipedia

How to recognize it

Achyra affinitalis, the cotton web spinner, belongs to the moth family Crambidae.

Source: Wikipedia

Size

The adult’s wingspan is roughly 20 mm.

Source: Wikipedia

Where it comes from

Its native range includes Australia and New Zealand.

Source: Wikipedia

More photos

Cotton Web Spinner photo 2
Photo: Jacqui Geux, CC BY
Cotton Web Spinner photo 3
Photo: Steve Kerr, CC BY
Cotton Web Spinner photo 4
Photo: Grey Smith, CC BY
Cotton Web Spinner photo 5
Photo: Possums' End, CC BY

Questions people ask

What plants do cotton web spinner larvae eat?

The caterpillars feed on sunflower, alfalfa, flax, cotton, sorghum and Atriplex species.

Source: Wikipedia

Where is the cotton web spinner found?

It occurs in Australia and New Zealand.

Source: Wikipedia

How big is the cotton web spinner?

Adults have a wingspan of about 20 mm.

Source: Wikipedia

What family does the cotton web spinner belong to?

It is a member of the moth family Crambidae.

Source: Wikipedia

Same family (Crambidae)

Box Tree MothBox Tree MothCydalima perspectalisDamages trees, gardens or cropsCelery Leaftier MothCelery Leaftier MothUdea rubigalisDamages trees, gardens or cropsElegant Grass-veneerElegant Grass-veneerMicrocrambus elegansHawaiian Beet Webworm MothHawaiian Beet Webworm MothSpoladea recurvalisDamages trees, gardens or cropsGarden Grass-veneerGarden Grass-veneerChrysoteuchia culmellaDamages trees, gardens or cropsBluegrass Webworm MothBluegrass Webworm MothParapediasia teterrellusDamages trees, gardens or crops

Sources

  • Wikipedia: https://en.wikipedia.org/wiki/Achyra_affinitalis

Look it up elsewhere: GBIF · iNaturalist · BugGuide · Wikipedia

Text written 2026-10-24 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-22.

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