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How to Manage Pests:
Pest Management and Identification
Convergent lady beetle
Scientific name: Hippodamia convergens
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Phylum: Arthropoda
Class: Insecta
Order: Coleoptera
Family: Coccinellidae
Common prey: Predaceous on aphids and occasionally other soft-bodied
homopterans. Used for aphid control in roses.
Can be important in every crop with aphid pests.
Commercially available: Yes
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Lady beetles are easily recognized by their shiny, convex, half-dome
shape and short, clubbed antennae. Most lady beetles, including this
species, are predaceous as both larvae and adults. Young lady beetle
larvae usually pierce and suck the contents from their prey. Older
larvae and adults chew and consume their entire prey. Larvae are active,
elongate, have long legs, and resemble tiny alligators. Many lady
beetles look alike and accurate identification requires a specialist.
Adult convergent lady beetles measure 4-7 mm (<1/4 inch) long
and have orange to red forewings, with up to 13 black spots; however,
many individuals have fewer spots and some have none. The thorax
is black with two converging white lines inside and a white margin.
The elongated larvae grow up to 7 mm (1/4 inch) long and are blackish
with orange spots. Eggs are oblong, yellow, measure about 1 mm (1/25
in) in length and are laid on end in groups on leaves and stems
near aphids. Pupation occurs in sheltered places on stems or other
substrates. Convergent lady beetles undergo complete metamorphosis
and have one or two generations per year.
Both adults and larvae of H. convergens feed primarily
on aphids and occasionally on whiteflies, other soft-bodied insects
and insect eggs. In California, many Hippodamia species overwinter
in large aggregations in the Sierra Nevada. In the spring, adults
fly down from the mountains to coastal and valley areas. Commercially
available Hippodamia are collected at overwintering sites
and can be bought and released. Unfortunately, lady beetles have
the tendency to disperse once they are released, even if food is
abundant. Although they are extremely important natural enemies
of aphids, their propensity to disperse makes it difficult for them
to be used in inoculative or inundative biological control programs.
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