Bug FAQTetracis formosa
Tetracis formosa · Order: Lepidoptera · Family: Geometridae
Tetracis formosa is a moth whose forewings are 17 to 23 mm long. It lives in western North America from Colorado and eastern Utah to California and up to southern British Columbia and Alberta, usually between 870 and 2,320 m elevation. The larvae feed on the shrub Prunus andersonii, and adults fly from early September to late November.
Source: Wikipedia
Size
The forewings measure about 17 to 23 mm long.
Source: Wikipedia
What it eats
Larvae have been raised on the shrub Prunus andersonii.
Source: Wikipedia
When you see it
Adults are on the wing from early September through late November.
Source: Wikipedia
Where it comes from
Its native range covers those same western North American regions.
Source: Wikipedia
Where it is found in the US
Recorded in 9 of 51 states and DC. Most records: Wyoming, Colorado, Montana, California, Utah, Idaho, Nevada, New Mexico.
Darker = more records. Counts are museum and citizen-science records, not population size.
Source: GBIF
Status: native in North America; native in Canada; native in United States. Source: iNaturalist
Months it is reported in the US
Source: GBIF
More photos
Questions people ask
When are adult Tetracis formosa moths active?
Adults can be seen flying from early September until late November.
Source: Wikipedia
Same family (Geometridae)
Sources
- Wikipedia: https://en.wikipedia.org/wiki/Tetracis_formosa
Look it up elsewhere: GBIF · iNaturalist · BugGuide · ITIS · Wikipedia
Text written 2026-10-26 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-26.