Altica carduorum - "Canada Thistle Beetle"

 

General/Historical:

 

Altica carduorum is a leaf beetle in the family Chrysomelidae, subfamily Alticinae. The genus Altica is very large, with at least 200 known species that are worldwide in distribution.

 

Plant Host(s):

 

Cirsium arvense (Linnaeus) Scopoli

 

Description/Biology:

 

Species of Altica are typically metallic in color, and the adults are small beetles. Overwintered adults lay eggs in small groups on the undersurface of leaves in late spring and early summer. Larvae feed on the leaves, then leave the stems during the third instar and pupate in the soil and duff. Adults appear in August and are active until the first fall frost. There is one generation per year.

 

Collection Techniques:

 

Adults can be collected by hand from the host plants.

 

Feeding Damage:

 

Altica carduorum feeding by adults and larvae results in skeletonization of leaves. Adults prefer to feed on the upper surfaces of leaves, and larvae feed on the undersides.

 

Operational Status:

 

Altica carduorum was released in 14 states (CA, CO, DE, ID, IN, MD, MN, MT, NV, NJ, OR, SD, WA, WI) in the U.S. in 1966 and three states in 1970 (MD, NJ, and SD), but did not become established.

 

Contact Personnel:

 

Don Joley

Biological Control Program

Integrated Pest Control

California Department of Food and Agriculture

3288 Meadowview Road

Sacramento, CA 95832

Phone: (916) 262-2054

 

Peter Harris

Lethbridge Research Station

P.O. Box 3000, Main

Lethbridge, Alberta

T1J 4B1

S4P 3A2

Phone: (403) 327-4561