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The butterfly
lifecycle
1 - Egg
- anatomy, oviposition
2 - Caterpillar
-
anatomy
3
- Caterpillar
- hatching, feeding and development
4
- Caterpillar
- cannibals, carnivores and myrmecophiles
5
- Caterpillar
- survival mechanisms,
armature, camouflage / disguise
6
- Caterpillar
-
co-evolution with plants
7
- Chrysalis
- pupation, metamorphosis
8
- Adult
- emergence, feeding
9
- Adult
- mate location and courtship
10 - Adult
- daily routine, roosting, hibernation, lifespan
Larva
: anatomy
Anatomy
A larva has only 2 functions during it's life - to
eat and survive. It's basically just an eating machine with large
powerful jaws, a huge gut, and a highly elastic skin that stretches to
accommodate the huge amount of food consumed.
Larvae do not possess external wings. Even the tiniest larvae however
have rudimentary wing-pads under their skin. These are initially
extremely small, but by the time the larvae are fully grown the wing
pads have developed veins and other structural features found in adult
butterflies.
Head of 5th instar Polyura hebe (
Nymphalidae ), Singapore
© Horace
Tan
All butterfly larvae
have six true legs located on the first 3 segments. These legs are
used primarily for holding and manipulating the leaves on which they
feed. On the abdominal segments they have 4 pairs of false legs
called prolegs. These "walking" legs operate by hydraulic pressure.
Each has a rosette of microscopic hooks around its base, which
enable the larvae to maintain a strong grip on twigs or leaves.
There are also a pair of gripping anal claspers at the tail end of
the body, which are used to secure the caterpillar while the prolegs
are doing the walking.
The spiracles can be seen clearly on this
Cerodirphia Saturniid larva from Peru ©
Adrian Hoskins
Caterpillars breathe through oval spiracles which open and close to
allow gas exchange with the atmosphere. There are 2 spiracles per
body segment, one on each side of the body.
Caterpillar of Privet Hawkmoth
Sphinx ligustri
( Sphingidae ), England ©
Adrian Hoskins
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