Medically reviewed and approved by a board-certified member
1) Chilopoda:
- Phylum Arthropoda includes this group Chilopoda.
- Chilopoda includes centipedes.
- These are dorso - ventrally flattened, distinctly segmented arthropods.
- The body shows 2 divisions. 1. head and 2. long trunk.
- The head bears a pair of long, many jointed, sensory antennae, a pair of eyes, a pair of toothed mandibles and two pairs of maxillae.
- The mouth lies on the ventral side near the anterior border of the head.
- The trunk contains 15-173 segments in different species.
- Each segment has a flat tergum on the dorsal side, sternum on the ventral side.
- Each trunk segment, except the last two, bears on its lateral sides a pair of legs. They are modified into stout poison claws or maxillipedes. They are used for killing the prey.
- The anus is situated at the extreme end of the trunk.
- There is a single genital opening.
- The genital opening opens in front of the anus on the ventral side of thepenultimate segment.
- A pair of long Malphighian take up excretion.
- Tracheae serve as respiratory organs.
- Sexes are separate, there is a single gonad above the alimentary canal. Ex: Scolopendra.
2. Diplopoda:
- Phylum Arthropoda includes this class.
- The class diplopoda includes the millipedes,
- These are long, cylindrical, segmented arthropods.
- Body has 3 divisions, head, thorax and abdomen.
- The head bears a pair of short, 7 jointed antennae, a pair of eyes, a pair of mandibles and a pair of maxillae.
- The maxillae are fused with the first thoracic sternum to form a large labium like structure called the Ganthochilarium.
- The mouth lies between the mandibles.
- The thorax is short and consists of four single segments.
- Each segment has an arched tergum and a small flat sternum.
- The abdomen is long and comprises 20 to 103 segments.
- Each segment bears two pairs of 7 jointed legs.
- The third abdominal segment bears in the male a pair of short gonads or auxilliary compulatory organs.
- There are two genital apertures that open out towards the anterior end on the third segment close to the second pair of legs (Progoneata).
- A pair of long malphighian tubules take up excretion.
- Tracheae will serve as respiratory organs.
- Sexes are separate. Ex: Julus
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