Bug FAQWhite-tipped Ctenucha
Ctenucha rubroscapus · Order: Lepidoptera · Family: Erebidae
Also called: Red-Shouldered Ctenucha
The white-tipped Ctenucha is a moth with black wings that have white tips and a striking red and black head and thorax; its abdomen shines iridescent blue. Adults fly at night in midsummer, preferring wet meadow habitats in low-elevation western North America west of the Cascades.
Source: Wikipedia
Size
Forewing length is about 19 to 20 mm.
Source: Wikipedia
Where it lives
Adults are nocturnal and are found in wet meadows where they feed on flowers.
Source: Wikipedia
What it eats
Larvae eat grasses, including species in the Poaceae and Cyperaceae families as well as Dactylis and Elymus.
Source: Wikipedia
Life cycle
The caterpillar is black with white hairs and has an orange head.
Source: Wikipedia
When you see it
Adults are on the wing at night during midsummer.
Source: Wikipedia
Where it is found in the US
Recorded in 3 of 51 states and DC. Most records: Oregon, California, Washington.
Darker = more records. Counts are museum and citizen-science records, not population size.
Source: GBIF
Status: native in North America; native in United States. Source: iNaturalist
Months it is reported in the US
Source: GBIF
More photos
Questions people ask
What do the larvae eat?
The larvae feed on grasses such as Poaceae, Cyperaceae, Dactylis and Elymus.
Source: Wikipedia
Same family (Erebidae)
Spongy MothLymantria disparDamages trees, gardens or crops
Fall Webworm MothHyphantria cuneaDamages trees, gardens or crops
Brown-tail MothEuproctis chrysorrhoeaCan irritate skin
Isabella Tiger MothPyrrharctia isabella
Virginian Tiger MothSpilosoma virginicaCan irritate skin
Salt Marsh MothEstigmene acreaSources
- Wikipedia: https://en.wikipedia.org/wiki/Ctenucha_rubroscapus
Look it up elsewhere: GBIF · iNaturalist · BugGuide · ITIS · Wikipedia
Text written 2026-10-24 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-24.