Acorn Weevil
Curculio glandium
This record describes Curculio glandium (species). Recorded family: Curculionidae. Recorded order: Coleoptera.
Identification and Appearance
Length 4 to 8 mm. The most striking feature of the acorn weevil is its elongated snout, known as a 'rostrum', which is longer in females than males. Adults have a brownish and patterned body. Weevils in this genus can be hard to tell apart. C. glandium has 3 segments in the bulbous end of its antennae whereas C. nucum has 4 segments. Curculio nucum and Curculio glandium are very similar but can be distinguished by the shape of the antennal club. C. glandium (on the left) has a narrower and more tapered club than C. nucum (on the right). Unless identified by a recognised expert, photographic evidence is required and the specimen should be examined with a microscope. In the comments box, state the key or ID method used. Note the beetle's size and describe the identifying characters. It is advisable to retain the specimen in case further checks are needed. The female uses the long rostrum (snout) to bore into the centre of an acorn to lay her egg. The larva feeds within the acorn and eventually bores its way out. The larvae are short, and cylindrical in shape, and move by means of ridges on the underside of the body. Relatively common, particularly in the south of Britain.
Wikipedia reference for Curculio glandium: https://en.wikipedia.org/wiki/Curculio_glandium.
Classification
- Kingdom
- Animalia
- Phylum
- Arthropoda
- Class
- Insecta
- Order
- Coleoptera
- Family
- Curculionidae
- Genus
- Curculio
Imported taxonomy record. Source availability varies; see the source references and editorial policy below.
Habitat and Range
Habitat
Lives in Oak trees.
Seasonal Activity
Peaking in summer and autumn.
Diet and Behavior
Life History
The female uses the long rostrum (snout) to bore into the centre of an acorn to lay her egg. The larva feeds within the acorn and eventually bores its way out. The larvae are short, and cylindrical in shape, and move by means of ridges on the underside of the body.
Additional species information
Recorded status
Relatively common, particularly in the south of Britain.
About Primitive Winged Insects: the wider group
Order-level background for Coleoptera, the group containing Curculio glandium. Species-specific details appear above.
Group overview
Coleoptera is the largest order of insects with over 400,000 described species, representing ~25% of all known animal species and ~40% of all insects. In the U.S. alone, nearly 30,000 beetle species have been identified.
Ecological role of the group
Beetles are prominent decomposers, especially in forests, breaking down dead wood and recycling nutrients. As predators, they reduce populations of pest insects. Many species are also important pollinators of flowering plants.
Economic and practical significance of the group
Beetles have major economic significance: leaf beetles (Chrysomelidae) and weevils (Curculionoidea) are among the most destructive agricultural pests globally, costing billions annually, while predatory species like ladybugs provide natural pest control.
Recorded sources for this group: Britannica, Smithsonian, NCSU Entomology. Imported estimates may describe particular regions or reporting periods.
Photos of Acorn Weevil (4)
Frequently Asked Questions About Acorn Weevil
What is Acorn Weevil?
Acorn Weevil (Curculio glandium) is a species in the family Curculionidae, within the order Coleoptera.
How big is Acorn Weevil?
4 to 8 mm. The most striking feature of the acorn weevil is its elongated snout, known as a 'rostrum', which is longer in females than males. Adults have a brownish and patterned body. Weevils in this genus can be hard to tell apart.
Where is Acorn Weevil found?
Habitat: Lives in Oak trees.
When is Acorn Weevil active?
Acorn Weevil: seasonal activity - Peaking in summer and autumn..
What is the life cycle of a Acorn Weevil?
The female uses the long rostrum (snout) to bore into the centre of an acorn to lay her egg. The larva feeds within the acorn and eventually bores its way out. The larvae are short, and cylindrical in shape, and move by means of ridges on the underside of the body.