phylum arthropoda

• Class Merostomata - horseshoe crab
• Class Pycnogonida - sea spider
• Class Arachnida - Mites, tick, spiders, scorpion.
• Class Cephalocardia - no eyes, carapace or abdominal appendages. True hermaphrodites only
• Class Remipedia - only one species described from the Bahamas.
• Class Branchiopoda - primitive crustaceans
• Somites are paired structures of mesoderm-derived epithelial blocks located on either sides of the embryonic midline, and they are formed by segmentation
• Subclass Ostracoda - they resemble tiny clams
• Subclass Copepoda - ex. calanus
• Subclass Cirripedia - ex. barnacles
• Class Malacostraca - largest class of crustacean
• Order Isopoda - Ex. Porcelliio – sow bugs; Armadillidium – pill bugs
• Order Amphipoda – body compressed laterally. Ex. Orchestra – beach fleas
• Order Decapoda – three pairs of maxillipeds; and five pairs of walking legs, the first is modified to form pincers or chelae. Ex. Crabs, shrimps, lobsters
• Class Diplopoda– subcylindrical body with two pairs of legs per segment; oviparous. Ex. Narceus – millipede
• Class Chilopoda - Ex. Scolopendra – centipede
• Class Symphyla – slender with long filiform antennae