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Comparative studies of natural groups of organisms

Distinctive features of class Chilopoda (e) Spiracles are located on the sides or
The following features distinguish top of the body.
centipedes from other members of the (f) Reproductive opening located on the
phylum Arthropoda: last body segment
(a) They have a flattened body with a
distinct head. However, other body Structure of centipede
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segments are similar, the trunk is not Centipedes have a head bearing eyes, one
obviously divided into thorax and pair of mouthparts (jaws), and one pair of
abdomen. antennae (Figure 3.50). The body consists
(b) They have one pair of legs per segment. of many segments, each of which bears

(c) They are carnivores, feeding mainly one pair of legs. The legs of the first body
on insects and worms. segment are modified into poisonous claws,

(d) Their first trunk segments have and are used for defence, as well as for
appendages, which are modified into a capturing and paralysing preys. They have
pair of venomous fangs. tracheae used for gas exchange.

Segment
Leg Antenna

Eye

Poisonous jaw
Last pair of leg with
hooks for defence
Figure 3.50: Structure of a centipede

Adaptations of the centipede to its (d) They have venomous claws for
mode of life defence and hunting.

Centipedes are adapted to a wide range of (e) They have legs for locomotion.
habitats in the following ways: (f) The last pair of legs has hooks for

(a) They are fast moving animals; this defence.
helps them to catch their prey.
Class Diplopoda
(b) They feed on insects, spiders, and The class Diplopoda consists of members
worms, which they hunt and paralyse with many legs; usually two pairs of legs
with a bite by their venomous claws.
per body segment in adults. An example of
(c) They have antennae for sensation. members of class Diplopoda is a millipede.

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