Download Insect Anatomy

Insect Anatomy
The short version
First, some terms
• Dorsal – the back (think dorsal fin in
sharks)
• Ventral – the front (the underbelly side of
the insect)
• Terminal – The end (you have a hand at
the terminal end of your arm)
DORSAL
TERMINAL
VENTRAL
Three parts
• Spiders, scorpions, most crustaceans
have two main body parts: the
cephalothorax, and the abdomen.
• Insects have 3: head, thorax, abdomen.
The head
• Most insects have 2 large compound eyes
• Some have ocelli - “mini eyes”, they only
sense light, can have anywhere from 0 to
12
• Antennae – most insects have 2 antennae,
some are long some short, some hairy,
some not, etc…
– Sense different things in different species
• The head can have many mouthparts
• 2 main mouthparts you need to know:
– Mandibles – chewing mouthparts (2)
– Proboscis – a tube used for piercing and
sucking
Thorax
• Three segments – prothorax (front),
mesothorax (middle), metathorax (end).
• Each segment has two legs.
– The legs have many segments, the feet are
made up of segments called tarsi, some have
claws.
• Not all segments are easily visible on all
insects.
• On some insects the top part of the
prothorax (pronotum) extends over the
rest of the thorax.
• The meso- and the metathorax can have
wings.
• Some insects have none, some have two,
some have four.
• The forewings on some insects are hard
wing covers called elytra.
• Wings can have wing veins (do not carry
blood)
Abdomen
• The abdomen has segments also.
• The abdomen holds most of the organs
(just like humans)
– Some have cerci (pincers) on the end, some
have prolegs (little fleshy things that look a
little like legs)
• Most female insects have an ovipositor to
lay eggs.