Bug FAQStraight-jawed Pedunculate Ground Beetle
Promecognathus crassus · Order: Coleoptera · Family: Carabidae
The straight-jawed pedunculate ground beetle lives along the Pacific coast from British Columbia to California. It uses its large jaws to eat millipedes, even those that produce cyanide and benzaldehyde, and tolerates those toxins.
Source: Wikipedia
Where it lives
Occurs on the Pacific coast from British Columbia down to California.
Source: Wikipedia
What it eats
Feeds on millipedes, including toxic species that release hydrogen cyanide and benzaldehyde, and can tolerate those toxins.
Source: Wikipedia
Where it comes from
Native to the Pacific coast of North America, spanning British Columbia to California.
Source: Wikipedia
Where it is found in the US
Recorded in 4 of 51 states and DC. Most records: Washington, California, Oregon, Kansas.
Darker = more records. Counts are museum and citizen-science records, not population size.
Source: GBIF
Status: native in North America; native in Canada. Source: iNaturalist
Months it is reported in the US
Source: GBIF
More photos
Questions people ask
What does the straight-jawed pedunculate ground beetle eat?
It eats millipedes, even those that produce cyanide and benzaldehyde, and can tolerate those toxins.
Source: Wikipedia
Where is this beetle found?
It lives along the Pacific coast from British Columbia to California.
Source: Wikipedia
Same family (Carabidae)
Sources
- Wikipedia: https://en.wikipedia.org/wiki/Promecognathus_crassus
Look it up elsewhere: GBIF · iNaturalist · BugGuide · ITIS · Wikipedia
Text written 2026-10-25 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-25.