

Coccinella septempunctata
(Coleoptera: Coccinellidae)
Sevenspotted Lady Beetle
The sevenspotted lady beetle, repeatedly introduced to North America
from Europe for the biological control of aphids, was established in the
early 1970s in New Jersey, apparently from an accidental introduction.
It has since spread naturally or been introduced to many northeastern
and north central states. C. septempunctata may be a more
effective predator than some native lady beetle species, displacing them
in some areas.
Appearance
Comparatively large (7-8 mm) with a white or pale spot on either
side of the head. The body is oval, and has a domed shape. The spot
pattern is usually 1-4-2, black on the orange or red forewings. Lady
beetle larvae are dark and alligator-like with three pairs of prominent
legs, growing to 7-8 mm in length. Eggs are spindle shaped and small,
about 1 mm long.
Habitat (Crops)
Aphid infested crops, including potatoes,
legumes, sweet corn, alfalfa, wheat, sorghum, and pecans.
Pests Attacked
Reported prey include pea, cowpea, green peach, potato, corn leaf,
melon aphids, and greenbug.
Life Cycle
Adults overwinter in protected sites near the fields where they fed
and reproduced. In spring, emerging beetles feed on aphids before
laying eggs. Females may lay from 200 to more than 1,000 eggs over a
one to three month period commencing in spring or early summer. Eggs
are usually deposited near prey such as aphids, often in small clusters
in protected sites on leaves and stems. The eggs are small (about 1 mm)
and spindle-shaped.
C. septempunctata larvae grow from
about 1 mm to 4-7 mm in length over a 10 to 30 day period depending on
the supply of aphids. Large larvae may travel up to 12 m in search of
prey. A second generation may appear about a month later. The pupal
stage may last from three to 12 days depending on the temperature.
In the northeastern United States, there are one to two generations per
year before the adults enter winter hibernation. Development from egg
to adult may take only two to three weeks, and adults, most abundant in
mid- to late summer, live for weeks or months, depending on the
location, availability of prey, and time of year.
Conservation
C. septempunctata is spreading to new areas each season.
Conservation can best be accomplished by following integrated pest
management guidelines as outlined in the tutorial of this guide.
Pesticide Susceptibility
Tolerance to some pesticides at recommended application rates is
likely. Overwintering adults may be less susceptible than active adults
and larvae.
Commercial Availability
This species has been mass reared, but at this time is not
commercially available.
Taken from:
Hoffmann, M.P. and Frodsham, A.C. (1993) Natural Enemies of
Vegetable Insect Pests. Cooperative Extension, Cornell University,
Ithaca, NY. 63 pp.
Additional References
Gordon, R.D. (1985) The Coccinellidae (Coleoptera) of America
North of Mexico. J. NY Entomol. Soc., 93: 1-912.
Habeck, D.H., Bennett, F.D., and Frank, J.H. (1990) Classical Biological Control
in the Southern United States. Southern Cooperative Series Bulletin No. 355,
IFAS Editorial, University of Florida, Gainesville, FL. 197 pp.
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author (if credited on the page you are using). A recommended form for citing this website is:
Weeden, C.R., A. M. Shelton, and M. P. Hoffman. Biological Control: A Guide to Natural Enemies in North America. http://www.nysaes.cornell.edu/ent/biocontrol/ accessed (date).
Suggestions, corrections, and/or comments are appreciated: Contact
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