ARTHROPODS

GENERAL CHARCTERISTICS

-Estimated 750-000 species

-Includes insects and crustaceans

-Have paired, jointed appendages

-Have a chintinous exoskeleton

-Grow by process  known as molting

-First animal life form to thrive on land

CLASSIFICATION

-The Phylum Arthropoda is subdivided into Superclasses

1. Superclass Trilobita (extinct)
2. Superclass Crustacea
   • Class Ostracoda
   • Class Branchiopoda
   • Class Cirripedia
3. Superclass Chelicerata
   • Class Merostomata
   • Class Arachnida
4. Superclass Myriapoda
5. Superclass Hexapoda
   • Class Insecta

     6. Minor Arthropod Groups

• • Onychophora
  • Tardigrada
  • Pycnogonida
  • Pentastomida

SPECIMIN

1.This is a fragment of a trilobyte thorax.  It is part of the Superclass Trilobita.