Bug FAQOak Curculio
Conotrachelus posticatus · Order: Coleoptera · Family: Curculionidae
Source: Wikipedia
The oak curculio is a small reddish-brown weevil about 4 mm long that lives in North America and spends its second winter as an adult under leaf litter. Females lay eggs inside oak acorns; the larvae feed inside the seed for 10 to 30 days, then adults emerge in late spring to early summer and repeat the cycle. Heavy infestations can reduce oak regeneration because the beetles destroy the seeds they feed on.
Source: Wikipedia
How to recognize it
The head is densely covered with tiny pits and it has a long snout that looks like an elephant’s trunk.
Source: Wikipedia
Is it a pest in the house?
Infestations can harm oak trees by destroying the seeds inside the acorns.
Source: Wikipedia
Where it lives
It is found throughout North America. Adults spend their second winter hidden under fallen leaves on the ground.
Source: Wikipedia
What it eats
Both larvae and adults feed on acorns; females deposit eggs inside the seeds.
Source: Wikipedia
Life cycle
The larval stage lasts 10 to 30 days before pupating. Adults emerge in late spring to early summer, lay eggs in acorns, and then overwinter again as adults.
Source: Wikipedia
When you see it
Adults are active in late spring and early summer.
Source: Wikipedia
Where it comes from
The oak curculio is native to North America.
Source: Wikipedia
Lookalikes
It can be confused with Conotrachelus lobatus, C. carinifer, and C. naso, which share a long median prothoracic ridge and similar body shape.
Source: Wikipedia
Where it is found in the US
Recorded in 35 of 51 states and DC. Most records: Georgia, Texas, New York, Massachusetts, Tennessee, Pennsylvania, North Carolina, Florida.
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
How does the oak curculio damage oak trees?
Females lay eggs inside acorns and the larvae eat the seed from inside, reducing viable oak seedlings.
Source: Wikipedia
What does the oak curculio look like?
It is a dark reddish-brown weevil about 4 mm long with a densely punctate head and a long snout resembling an elephant’s trunk.
Source: Wikipedia
What other bugs might be mistaken for the oak curculio?
It resembles Conotrachelus lobatus, C. carinifer, and C. naso, which have similar body ridges.
Source: Wikipedia
Same family (Curculionidae)
Green Immigrant Leaf WeevilPolydrusus formosusDamages trees, gardens or crops
Black Vine WeevilOtiorhynchus sulcatusDamages trees, gardens or crops
Nettle weevilPhyllobius pomaceusDamages trees, gardens or crops
Asian Oak WeevilCyrtepistomus castaneusDamages trees, gardens or crops
Strawberry Root WeevilOtiorhynchus ovatusDamages trees, gardens or crops
Common Leaf WeevilPhyllobius pyriDamages trees, gardens or cropsSources
- Wikipedia: https://en.wikipedia.org/wiki/Conotrachelus_posticatus
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.