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

    Bryozoans (Moss Animals)

    Freshwater species in the phylum Bryozoa
    Photograph of Ebonyshell freshwater mussel shell exterior view

    Ebonyshell

    Fusconaia ebena
    exclamation mark

    Endangered

    Monkey Face Mussel

    Freshwater Mussels

    Bivalve molluscs in order Unionoida
    giant floater

    Giant Floater

    Pygandon grandis
    Photo of hellgrammite

    Hellgrammite

    Corydalus cornutus
    Photo of a horsehair worm in an aquarium

    Horsehair Worms

    About 350 species scientifically described.
    pistolgrip

    Pistolgrip (Buckhorn)

    Tritogonia verrucosa
    threeridge

    Threeridge

    Amblema plicata
    Photo of a pink planarian on a rock.

    Turbellarians (Planarians; Free-Living Flatworms)

    Species in genera Dugesia, Planaria, etc.
    Photo of a water scorpion, genus Ranatra, captured in a jar of pond water.

    Water Scorpions

    Ranatra spp. and Nepa apiculata