1. Phylum /
Group
Common
Name
Distinguishing
Characteristics
Porifera sponges Pore-bearing
animals
Cnidaria hydras Hollow-intestined
animals
Platyhel-
minthes
flatworms
tapeworms
Flattened,
elongated,
wormlike animals

2. Phylum /
Group
Common
Name
Distinguishing
Characteristics
Annelids earthworms
leeches
Elongated,
wormlike animals
with externally
evident
segmentation,
ringed animals
Mollusks snails, clams,
squid
Soft-bodied
animals, usually

3. 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

4. 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

5. 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

6. Identify the class to which each of these animals
belong using the Phylum Arthropoda Classification
Key
1. 3.
2. 4.

7. 5. 8.
6. 9.
7. 10.