Cancer

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 CANCER



CLASSIFICATION

PHYLUM: ARTHROPODA (Jointed appendages).

SUB-PHYLUM: CRUSTACEA (Biramous appendages).

CLASS: MALACOSTRACA (carapace cover head or thorax).


COMMENTS:

•Commonly known as "crabs" & are found buried under rocks, wood piece and in sand along sea shore.

•Body is flat & covered by a carapace. It is comprised of a cephalothorax of 13 segments & abdomen is curved below the cephalothorex.

• The cephalothorax is comprised of 13 (5+8) segments of cephalic & thoracic region.

•Carapace in Callinectes is beautifully decorated and is produced into a pair of spines laterally.

•The cephalothorax bears a pair of complex compound eyes, a pair of small antennule & antennae.

•The 5 pairs of walking legs, 1st pair is chelate & is largest.

• Abdominal appendages are degenerate, two pair of pleopods are present in males modified into coapulatory organs.

•Sexes are separate and development is indirect.




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