✓ Largest phylum of Kingdom Animalia.
✓ Over two thirds of all species on the earth are Arthropods.
Phylum – ArthropodaArthros=joint, podos= foot/appendages
✓ Organ-system level of organization, bilaterally
symmetrical, triploblastic, segmented coelomate
animals.(Haemocoelomates)
✓ Body is covered by thick chitinous exoskeleton to which
the muscles are attached.
✓ Body bears paired jointed appendages.
✓ Body consists of head, thorax and abdomen.
✓ Respiratory organs
1.gills,-(Prawn)
2.book gills,-(Limulus)
3.book lungs(Spider)
4.tracheal systems (Cockroach)
✓ Circulatory system open type.
✓ Digestive system complete.
✓ Sensory organs - antennae, eyes (compound and simple), sound receptors in crickets,statocysts or
balance organs are present.
✓ Nervous system consists of a dorsal brain and a ventral, ganglionated longitudinal nerve cord from
which lateral nerves extend in each segment.
✓ Excretion takes place through malpighian tubules.
✓ Sexes are separate (Dioecious).
✓ Fertilisation internal (terrestrial forms) and external (aquatic forms).
✓ They are mostly oviparous.
✓ Development may be direct(cockroach) or indirect (insects)
✓ Shows moulting (ecdysis).
Examples:
• Economically important:
Apis (Honey bee)
Bombyx (Silkworm)
Laccifer (Lac insect)
• Vectors:
Anopheles
Culex
Aedes (Mosquitoes)
• Gregarious pest:
Locusta (Locust)
• Living fossil: Limulus (King crab).
Apis (Honey bee) Bombyx (Silkworm)
Laccifer (Lac insect)
Musca domestica(house fly)
Limulus (King crab) Locusta (Locust)
Periplanata(cockroach)
Cancer (crab)Penaeus (prawn)
Eupagurus(Hermit crab) Lepisma(silver fish)Scorpion
Millipede Centipede
recap
❑ PHYLUM – ARTHROPODA✓ Largest phylum of Kingdom Animalia
✓ Body is covered by thick chitinous
exoskeleton to which the muscles are
attached.
✓ Body bears paired jointed appendages.
✓ Body consists of head, thorax and abdomen.
✓ Sensory organs - antennae, eyes (compound
and simple), sound receptors in crickets,
statocysts or balance organs are present.
✓ Excretion takes place through malpighian
tubules.
