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The
Cerambycidae, or long-horned beetles, get their common
name from their antennae. Characteristic of this family
is that the antennae are inserted in close proximity to
the eyes, so that most have an indentation of the eye.
Tetraopes carries this to the extreme, so that
the antennae actually split each eye in two, hence its
name. Tetraopes is one of the few insects that can
safely feed on milkweed. (Asclepias spp.) Others include
the Monarch butterfly
caterpillar and the milkweed leaf beetle,
Labidomera clivicollis.
"Plant chemical defenses
can be eaten by herbivores, stored, and used in defense against
predators. To be effective defensive agents, the
sequestered chemicals cannot be metabolized into inactive
products. Utilizing plant chemicals can be costly to herbivores
because it often requires specialized handling, storage, and
modification (Bowers 1992). This cost can be seen when plants
that utilize plant chemicals are compared to those plants that
do not in a situation where herbivores are excluded. Caterpillar
and adult
monarch butterflies
store
cardiac glycosides from
milkweed, making these organisms distasteful.
After eating a monarch caterpillar or butterfly, its bird
predator will vomit and will avoid eating similar individuals in
the future (Huheey 1984).
Species that feed on milkweeds are
usually
aposematically colored.
Aposomatic species are those that “advertise” their
distastefulness by being brightly colored (see Guilford 1990).
Two different species of milkweed bug in the family
Hemiptera,
Lygaeus
kalmii and
Oncopeltus fasciatus, are thus colored, with bright orange
and black markings."
From Wikipedia "Herbivore
adaptations to plant defense."
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