Limulus

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CLASSIFICATION:

Phylum :Arthropoda (Jointed legs)

Subphylum :Chelecerata (Feeding appendages called chelicerae)

Class : Merostomata (exhibit pseudocopulation during mating).


COMMENTS:

• It is commonly known as king crab & it is a marine arthopod found burrowing in sand.

• Body is comprised of anterior cephalothorax or prosoma & a posterior-opisthosoma.

•Cephalothorax is broad, convex above & concave below & bears a pair of median & a pair of lateral eyes andthree longitudinal ridges above.

•It also bears six pairs of non-locomotor limbs below around the mouth. All the legs,except the last pair, are chelate.

•The opisthosoma is divided into mesosoma, metasoma & belson & is movably articulated with prosoma.

• The first pair of appendages is united to form a genital operculum whereas remaining five pairs bear book gills or book lungs.

• Malphigian tubules absent & excreation through coxal glands.

•Regarded as living fossil. Indirect development.





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