Larinus minutus

Taxobox
name = "Larinus minutus"


image_width = 240px
regnum = Animalia
phylum = Arthropoda
classis = Insecta
ordo = Coleoptera
familia = Curculionidae
subfamilia = Lixinae
genus = "Larinus"
species = "L. minutus"
binomial = "Larinus minutus"
binomial_authority = Gyllenhal

"Larinus minutus" is a species of true weevil known as the lesser knapweed flower weevil. It is used as an agent of biological pest control against noxious knapweeds, especially diffuse knapweed ("Centaurea diffusa").

The adult weevil is dark mottled brown with a long snout. It is 4 or 5 millimeters long in total. It is active throughout the summer with a 14-week maximum adult lifespan. During this time the female lays up to 130 eggs, depositing them in the knapweed flower head. The larva emerges and burrows into the flower head where it feeds on the developing seeds. The larva damages the plant by reducing seed production and the adult does damage by defoliating the plant as it feeds on the leaves.

This weevil is native to southern Europe and the Mediterranean. It was first released as a knapweed biocontrol in the United States in the early 1990s. It is now established in knapweed populations throughout the western United States, especially in warm, dry areas. It feeds on knapweeds, preferring diffuse knapweed over others, and it has not been shown to attack native flora. This weevil has been shown to reduce diffuse knapweed density at several sites.

External links

* [http://www.nysaes.cornell.edu/ent/biocontrol/weedfeeders/larinus_minutus.html Cornell Biocontrol Profile]

References

Coombs, E. M., et al., Eds. (2004). "Biological Control of Invasive Plants in the United States". Corvallis: Oregon State University Press, 214.