Photo of backswimmer, side view

    Backswimmers

    About 32 North American species in the family Notonectidae
    Bluefer

    Bluefer (Purpleshell)

    Potamilus purpuratus
    Gray, speckled, translucent gelatinous blob cut in half to show structure

    Bryozoans (Moss Animals)

    Freshwater species in the phylum Bryozoa
    Photo of a papershell crayfish, also called calico crayfish.

    Calico Crayfish (Papershell Crayfish)

    Faxonius immunis (formerly Orconectes immunis)
    Monkey Face Mussel

    Freshwater Mussels

    Bivalve molluscs in order Unionoida
    No photo available

    Hydras

    Various species in the genus Hydra
    lilliput

    Lilliput

    Toxolasma parvus
    Photo of a ramshorn snail on a wet rock.

    Ramshorn Snails

    Gyraulus, Helisoma, Menetus, Micromenetus, Planorbula spp.
    Color illustration of Taillight Shiner

    Taillight Shiner

    Notropis maculatus
    exclamation mark

    Endangered

    Photo of an aquatic tubificid worm among rocks in an aquarium.

    Tubificid Worms (Tubifex Worms)

    Tubifex spp. and other aquatic tubificid annelids
    Photo of a pink planarian on a rock.

    Turbellarians (Planarians; Free-Living Flatworms)

    Species in genera Dugesia, Planaria, etc.
    Water springtails congregate in water above soggy dead leaves

    Water Springtail

    Podura aquatica