Phylum / Group

Common Name

Distinguishing Characteristics

Porifera sponges Pore-bearing animals

Cnidaria hydras Hollow-intestined animals

Platyhel-minthes

flatwormstapeworms

Flattened, elongated, wormlike animals

Phylum / Group

Common Name

Distinguishing Characteristics

Annelids earthwormsleeches

Elongated, wormlike animals with externally evident segmentation, ringed animals

Mollusks snails, clams, squid

Soft-bodied animals, usually

Phylum / Group

Common Name

Distinguishing Characteristics

Mollusks snails, clams, squid

living in a shell or exoskeleton

Nematodes roundworms Elongated, un segmented wormlike animals threadlike animals

Phylum / Group

Common Name

Distinguishing Characteristics

Arthropods insects, crabs, spiders,

centipedes

Segmented animals with hardened outer skeleton and jointed appendages

Echino-derms

starfish, sea urchin

Spiny-skinned animals

Arthropods

Five or more pairs of legs

Three pairs of legs

Four pairs of legs

One pair of legs per segment

Two pairs of legs per segment

Class Crustacean

Class Insecta

Class Arachnida

Class Chilopoda

Class Diplopoda

Identify the class to which each of these animals belong using the Phylum Arthropoda Classification Key

1. 3.

2. 4.

5. 8.

6. 9.

7. 10.