Predaceous ground beetles–Family Carabidae
Predaceous ground beetles are very common garden insects that feed on many soil-inhabiting pests such
as cutworms and root maggots. One species even feeds on the brown garden snail. Shapes and colors vary
widely but carabids are usually shiny. Some species are black, but other species may be marked with bright
colors. Be sure to distinguish them from darkling beetles, which are common pests of seedlings. Darkling
beetles are dull and the segments on the tips of their antennae are slightly larger than those at the
base; carabid antennae rarely have enlarged antennal segments. Predaceous ground beetles can be distinguished
from plant-feeding darkling beetles by examining the spot where their hind legs meet their abdomen. Ground
beetles have enlarged basal segments on their hind legs; the hind leg coxae completely divide or cover
at least the first abdominal segment. The rear margin of the first abdominal segment of the darkling beetle
is entirely visible and the hind coxae and trochanters are not enlarged.
Carabid larvae have 10 well-defined, abdominal segments, a large head with prominent mandibles, and
four-segmented antennae. The body tapers toward the rear with prominent appendages (cerci). An anal tube
on the ninth segment is visible as a stubby pale protuberance between the cerci.
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