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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 close up of a Saturniid larva,
Cerodirphia sp,
from Peru.
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 ), Hampshire, England.
3 -
Hatching, feeding and development >>>
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