Bug FAQAgreeable Caterpillar Hunter
Calosoma sycophanta · Order: Coleoptera · Family: Carabidae
Also called: Forest Caterpillar Hunter, Fiery Searcher, Ground beetle
The Agreeable Caterpillar Hunter is a large ground beetle about 2 to 3.5 cm long with metallic green elytra and a black head that shows iridescent shades of blue, bronze, copper and gold in the light. It lives in trees throughout Europe, the Near East, North Africa, the eastern Palearctic and parts of the Nearctic, where both adults and larvae hunt caterpillars during the day.
Source: Wikipedia
How to recognize it
The beetle’s wing covers are a bright metallic green, while the small scutellum behind them is metallic blue. Its head is black and the whole body shows iridescent colours that shift with the light.
Source: Wikipedia
Size
Adults measure between about 21 and 35 mm in length.
Source: Wikipedia
Where it lives
Both the adult beetles and their larvae live in trees.
Source: Wikipedia
What it eats
It feeds voraciously on caterpillars such as the gypsy moth, processionary moths and the brown-tail moth, both as a larva and as an adult.
Source: Wikipedia
Life cycle
Both life stages to larvae and adults to reside in trees.
Source: Wikipedia
When you see it
The beetle is active during daylight hours.
Source: Wikipedia
Where it comes from
It is native to Europe. The species is also found across most European countries, the eastern Palearctic, the Nearctic, the Near East and North Africa.
Source: Wikipedia
Where it is found in the US
Recorded in 14 of 51 states and DC. Most records: New Jersey, Massachusetts, New York, Pennsylvania, New Hampshire, Vermont, Maine, Rhode Island.
Darker = more records. Counts are museum and citizen-science records, not population size.
Source: GBIF
Status: introduced in North America; introduced in United States. Source: iNaturalist
Months it is reported in the US
Source: GBIF
More photos
Questions people ask
What does the Agreeable Caterpillar Hunter eat?
It hunts and eats a range of caterpillars, including gypsy moth and processionary moth larvae, both as a larva and as an adult.
Source: Wikipedia
Where can I find this beetle?
It lives in trees across Europe, the Near East, North Africa, the eastern Palearctic and parts of the Nearctic.
Source: Wikipedia
Same family (Carabidae)
Sources
- Wikipedia: https://en.wikipedia.org/wiki/Calosoma_sycophanta
Look it up elsewhere: GBIF · iNaturalist · BugGuide · ITIS · Wikipedia
Text written 2026-10-27 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-27.