Water Animals

1. Microscopic (a microscope is needed to see any real detail on the organism)Go to #2
Macroscopic (easily visible with only your eyes, anatomy can be detailed)Go to #6
2. Microscopic round or oval animalsGo to #3
Microscopic worm-like animalsGo to #4
Microscopic elongated animals with legs, tentacles, or spinesGo to #5
3. Single celled organismsProtozoans
Round shelled animals with legs and antennaeSmall Crustaceans

Photograph of a protozoan
protozoans		 Photograph of a small crustacean
small crustaceans

4. Elongated worms with very pointed ends, no segmentationRoundworms
Microscopic worms that frequently have eyes spots or a mouthFlatworms
Worm-shaped animals that swim with cilia and a forked tail, round mouth in the head areaGastrotrichs
Worms with suckers on each end of their bodyLeeches
Reddish worms with a segmented body that frequently has hairs on itAquatic Worms
Worm-like animals with bodies in sections, cilia on the head and a distinctive foot on the other endRotifers

Photograph of a flatworm
flatworms		 Photograph of a gastrotrich
gastrotrichs		 Photograph of an aquatic worm
aquatic worms
5. Microscopic insects with 6 legsSpringtails
Microscopic animals with 8 legsTicks & Mites
Microscopic animals that look like slivers of glass with patches of cells on themSponges
Microscopic animals with a trunk-like body with several tentaclesHydras & Jellyfish
Microscopic animals with many legs and prominent antennaeSmall Crustaceans

Photograph of a springtail
springtails		 Photograph of a sponge
sponges		 Photograph of an small crustacean
small crustaceans

6. Easily visible animals with a beige crust and hair-like extensionsSponges
Macroscopic worm shaped animalsGo to #7
Snails or clams with a large prominent shellMollusks
Larger animals with finsFish
Larger animals with legsGo to #8

Photograph of a sponge
sponges		 Photograph of a mollusk
mollusks

7. Worms with suckers on each end of their bodyLeeches
Insects with a segmented, hard outer shell, that may live in tubesLegless Aquatic Insects & Tube Dwellers
Large vertebrate animals with a prominent mouthSnakes

8. Animals with 6 legs Aquatic Insects
Animals with many legs present and prominent antennae and shellsSmall Crustaceans
Lobster-like animals with large clawsCrayfish
Animals with 4 legs or 2 legs and 2 wings (Vertebrates)Go to #9

Photograph of a aquatic insect
aquatic insects		 Photograph of a small crustacean
small crustaceans		 Photograph of an crayfish
crayfish

9. Animals with moist skin or scalesReptiles & Amphibians
Animals with feathersWater Birds
Animals with furWater Mammals