''Curculio occidentis'', the filbert weevil, is a species of

weevil Weevils are beetles belonging to the Taxonomic rank, superfamily Curculionoidea, known for their elongated snouts. They are usually small, less than in length, and Herbivore, herbivorous. Approximately 97,000 species of weevils are known. They b ...

in the genus '' Curculio''. The weevils are considered a

pest Pest or The Pest may refer to: Science and medicine * Pest (organism), an animal or plant deemed to be detrimental to humans or human concerns ** Weed, a plant considered undesirable * Infectious disease, an illness resulting from an infection ** ...

for many species of

oak An oak is a tree or shrub in the genus ''Quercus'' (; Latin "oak tree") of the beech family, Fagaceae. There are approximately 500 extant species of oaks. The common name "oak" also appears in the names of species in related genera, notably ''L ...

tree due to the damage they cause to

acorn The acorn, or oaknut, is the nut of the oaks and their close relatives (genera ''Quercus'' and '' Lithocarpus'', in the family Fagaceae). It usually contains one seed (occasionally two seeds), enclosed in a tough, leathery shell, and borne ...

s.Filbert Pests in Live Oaks
University of California.

Distribution

''Curculio occidentis'' is native to the western side of North America. Its range includes

British Columbia British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, ...

in Canada,

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

Arizona Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a state in the Southwestern United States. It is the 6th largest and the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona is part of the Fou ...

New Mexico ) , population_demonym = New Mexican ( es, Neomexicano, Neomejicano, Nuevo Mexicano) , seat = Santa Fe , LargestCity = Albuquerque , LargestMetro = Tiguex , OfficialLang = None , Languages = English, Spanish ( New Mexican), Navajo, Ker ...

and

Utah Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to it ...

in the United States, and Mexico.

Ecology

The female ''Curculio occidentis'' lays small batches of two to four eggs in a developing acorn. The resulting

larva A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. The ...

e feed on the kernel and when fully developed, tunnel out of the nut, fall to the ground and dig themselves a small chamber. They may wait one or two years before

pupa A pupa ( la, pupa, "doll"; plural: ''pupae'') is the life stage of some insects undergoing transformation between immature and mature stages. Insects that go through a pupal stage are holometabolous: they go through four distinct stages in their ...

ting. Garry oak acorns were collected in 1996, 1997 (low crop years) and in 1998 (high crop year) to examine infestation damage. It was concluded that levels of infestation did not vary with crown level during the low crop years but varied during the high crop year. Affected acorns were more present at the lower portion of the tree than the upper part of the tree during the high crop year. Together with larva of the filbertworm moth (''Cydia latiferreana''), the filbert weevil feeds on the acorns of several species of oak tree. In British Columbia, up to 66% of acorns from garry oak (''Quercus garryana'') were infected with these larvae. These acorns are still able to germinate, but the germination rate is lower than for uninfected nuts.

References

External links

bugguide.net
*
discoverlife.org

wiki.pestinfo.org

sbnature.org
Curculioninae Beetles of North America Agricultural pest insects Beetles described in 1758 Taxa named by Carl Linnaeus {{Curculioninae-stub