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Sars 1903


Phylum Arthropoda
Subphylum Crustacea
Class Malacostraca
Superorder Eucarida
Order Decapoda

Distinguishing characteristics

  • 8 pairs of thoracic appendages.
  • Five pairs of appendages are considered as the 10 legs (pereiopods), hence the name Decapoda).
  • Front 3 pairs of appendages function as mouthparts (maxillipeds).
  • 1 pair of legs (chelipeds) are enlarged pincers (claws called chalae).
  • Other appendages located on abdomen where each segment is capable of carrying biramous pleopods.
  • Last pleopods form part of the tail fan, and together with the telson are called uropods.
  • Classification depends on structure of gills and legs, and larval development.


  • 8,000 species worldwide.
  • Most abundant in shallow warm waters.
  • Mostly scavengers.
  • Four basic larval types distinguished partly by mode of locomotion: nauplius, protozoea, zoea, and postlarva. Most larvae hatch at the zoea stage.