1st Instar
Egg
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1st Instar
|
2nd Instar
|
3rd Instar
|
4th Instar
|
5th Instar
Specifications
Body and Head (x20)
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Body Length:
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2 to 6 mm
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Body Width:
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0.5 to 1.5 mm
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Front Tentacles:
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Small bumps
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Back Tentacles:
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Barely visible
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Head Capsule:
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0.6 mm in diameter
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Appearance
A newly-hatched monarch larva is pale green or grayish-white, shiny, and almost
translucent. It has no stripes or other markings. The head looks black, with lighter
spots around the antennae and below the mouthparts, and may be wider than the body.
There is a pair of dark triangular patches between the head and front tentacles
which contain setae, or hairs. The body is covered with sparse setae. Older first
instar larvae have dark stripes on a greenish background.
After hatching, the larva eats its eggshell (chorion). It then eats clusters of
fine hairs on the bottom of the milkweed leaf before starting in on the leaf itself.
It feeds in a circular motion, often leaving a characteristic, arc-shaped hole in
the leaf. First (and second) instar larvae often respond to disturbance by dropping
off the leaf on a silk thread, and hanging suspended in the air.
Color Pictures
