Curculio occidentis
{{Short description|Species of beetle}}
{{Speciesbox
| name = Filbert weevil
| image = Kaldari Curculio occidentis 01.jpg
| image_caption = A filbert weevil (Curculio occidentis) on an acorn cap
| genus = Curculio
| species = occidentis
}}
Curculio occidentis, the filbert weevil, is a species of weevil in the genus Curculio. The weevils are considered a pest for many species of oak tree due to the damage they cause to acorns.[http://ucanr.edu/sites/oak_range/Oak_Articles_On_Line/Oak_Pest_Management/Filbert_Pests_in_Live_Oaks/ Filbert Pests in Live Oaks], University of California.{{Cite journal|url=http://viuspace.viu.ca/handle/10613/65|title=The Effects of the Filbert Weevil (Curculio occidentis) and the Filbertworm (Cydia latiferreana) on Garry Oak (Quercus garryana) Acorn Germination on Vancouver Island|last=Waller|first=Jennifer|date=2010|website=viuspace.viu.ca|publisher=Vancouver Island University|language=en|doi=10.25316/IR-A7|access-date=2016-01-08}}
Distribution
Curculio occidentis is native to the western side of North America. Its range includes British Columbia in Canada, California, Arizona, New Mexico and Utah in the United States, and Mexico.{{cite book|author=David Hagstrum|title=Stored-Product Insect Resource|url=https://books.google.com/books?id=TklhDAAAQBAJ&pg=PA68 |year=2009 |publisher=Elsevier |isbn=978-0-12-810456-9 |page=68}}
Ecology
The female Curculio occidentis lays small batches of two to four eggs in a developing acorn. The resulting larvae 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 pupating.{{cite book|author=Cranshaw, Whitney|title=Garden Insects of North America: The Ultimate Guide to Backyard Bugs|url=https://books.google.com/books?id=RITYBQAAQBAJ&pg=PA282 |year=2015|publisher=Princeton University Press |isbn=978-1-4008-6678-6 |pages=282}} 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. {{cite journal | last1 = Otvos | first1 = Imre S. | last2 = Mills | first2 = Doris A. | last3 = Conder | first3 = Nicholas | title = Within-crown distribution, attack, and germination of Curculio occidentis-damaged and Cydia latiferreana-damaged Garry oak acorns in Victoria, British Columbia, Canada | journal = The Canadian Entomologist | date = 28 May 2012 | volume = 144 | issue = 3 | pages = 419–434 | issn = 0008-347X | eissn = 1918-3240 | doi = 10.4039/tce.2012.43 | pmid = | s2cid = 85198349 | url = }}
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
{{Reflist}}
External links
- [http://bugguide.net/node/view/495006/bgpage bugguide.net]
- {{CalPhotos|Curculio|occidentis}}
- [http://www.discoverlife.org/mp/20q?search=Curculio+occidentis discoverlife.org]
- [http://wiki.pestinfo.org/wiki/Curculio_occidentis wiki.pestinfo.org]
- [https://web.archive.org/web/20130323193944/http://www.sbnature.org/collections/invert/entom/s_p_curcu_occid.php sbnature.org]
{{Taxonbar|from=Q10858402}}
Category:Beetles of North America
Category:Agricultural pest insects
Category:Beetles described in 1758
Category:Taxa named by Carl Linnaeus
{{Curculioninae-stub}}