Nanophyes brevis
      Coleoptra: Curculiondae 
      Pictures:  Sorry, we couldn't find any pictures.  If you have some, feel free to send them. 
      LIFE CYCLE:
      Overwintering Stages:  Egg to larval, to pupae or adult. (3)
      Egg stage:  A female lays eggs into the ovaries of a flower that is opened and fertilized. (3)
      Larval Stage:  Over a seven week period, the larvae eats the developing seeds that are in the ovaries. (3)
      Pupal Stage:  This stage takes place inside the flower's ovaries. (3)
      Adult Stage:  This insect is about 2 to 2.5 cm long.  They are reddish with colored spots on their shoulders and have a long snout and a blunt abdomen.  During August and September, you can find the adults.  The adults leave the seeds by chewing their way through the walls.  The adults look for places to winter in old plants and in the soil.  The insects then resume their normal activities when the next May comes.  These weevils usually stay on the lower half of the flower. (3)

      Type of Damage to Host:  The weevils attack during the adult and larval stages.  They attack purple loosestrife.  The adults feed on the young stem leaves and on immature seed capsules that stay on the flower spikes.  The larvae feed on the growing seeds.  The eating of the seed capsules by the adults causes them to fall off.  This is what stops further seed developement. (3)  The seed developement and production is reduced by 50% (3,2) or 60%. (1)

      Redistribution:  A sweep net or a beating tray and stick can be used to get the weevils off of the plants.  The best time to collect is in August and September.  It is recommended that you release 100-200 insects for a good chance of establishment. (3)

      Remarks:  Introduction of this insect has been delayed beacuse of a nemotode that infected the species in Europe. (1,3)

      Sources:
      1.  Washington State Department. Non Native Freshwater Plants Purple Loosestrife. Available http://www.ecy.wa.gov/programs/wq/plants/weeds/agua009.html. Information downloaded January 3, 2002.

      2.  Youth Stewardship in Environmental Sciences Project. Purple Loosestrife. Available http://www.uwinnipeg.ca/~simmons/ysesp/exotic2.htm. Information downloaded January 4, 2002.

      3.  Rees Norman, et, al., ED., Biological Control of Weeds in the West, Western Society of Science, in copperation with USDA, ARS, MT Department of Ag. and MT State Univ. Bozeman, Color World Printers, Bozeman MT, Feb, 1996 

       Links:
      1:IVM Technical Bulletin,
      2:Cornell University,
      3:The Western Aquatic Plant Panagemnt Society
      4:Introduced Biological Control Agents of Weeds in Montana,
      5:Purple Loosestrife
      6:Youth Stewardship in Environmental Sciences Project,
      7:Washington State Department,
      8:University of Wisconsin-Madison
      9:Great Plains
      10:Invasive Plants
      By: Crane, Billy & Lack, Tyler 
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