Bug FAQBroadhorned Flour Beetle
Gnatocerus cornutus · Order: Coleoptera · Family: Tenebrionidae
Also called: Broad-horned Flour Beetle
Source: Wikipedia
It lives worldwide in stored-product environments, especially warm tropical areas and flour mills in cooler regions, feeding on grains, yeasts and flours. Its life cycle includes egg, larva, pupa and adult stages and takes about 47 days to develop.
Source: Wikipedia
Is it a pest in the house?
It is a common storage pest in mills and other food-storage facilities worldwide, preferring grains, yeasts and flours.
Source: Wikipedia
Where it lives
It is a stored-product insect found worldwide, especially in warm, tropical regions. In warm areas it is often found in cassava and cotton, while in temperate places like the UK it occurs in flour and provender mills.
Source: Wikipedia
What it eats
It mainly feeds on various grains, yeasts and flours.
Source: Wikipedia
Life cycle
It goes through four stages: egg, larva, pupa and adult. The complete development takes about 47 days.
Source: Wikipedia
Where it comes from
The species has a worldwide distribution.
Source: Wikipedia
Where it is found in the US
Recorded in 41 of 51 states and DC. Most records: Ohio, Michigan, New York, Pennsylvania, Florida, Wisconsin, Texas, Illinois.
Darker = more records. Counts are museum and citizen-science records, not population size.
Source: GBIF
Status: introduced in Canada; native in North America. Source: iNaturalist
Months it is reported in the US
Source: GBIF
Questions people ask
How big are broadhorned flour beetles?
Adults measure about 3.5 to 4.5 mm in length.
Source: Wikipedia
Where are broadhorned flour beetles usually found?
They are found worldwide in stored-product settings, especially in warm tropical areas and in flour mills in cooler regions.
Source: Wikipedia
What do broadhorned flour beetles eat?
They feed mainly on grains, yeasts and flours.
Source: Wikipedia
Same family (Tenebrionidae)
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Sources
- Wikipedia: https://en.wikipedia.org/wiki/Gnatocerus_cornutus
Look it up elsewhere: GBIF · iNaturalist · BugGuide · Wikipedia
Text written 2026-10-23 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-23.