brokenray

    Arkansas Brokenray

    Lampsilis reeveiana
    Photo of a bristly cave crayfish, viewed from the side.

    Bristly Cave Crayfish

    Cambarus setosus
    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)
    deertoe

    Deertoe

    Truncilla truncata
    elephant's ear

    Elephantear

    Elliptio crassidens
    exclamation mark

    Endangered

    elktoe

    Elktoe

    Alasmidonta marginata
    ellipse

    Ellipse and Bleedingtooth

    Venustaconcha ellipsiformis and V. pleasii
    Monkey Face Mussel

    Freshwater Mussels

    Bivalve molluscs in order Unionoida
    giant floater

    Giant Floater

    Pygandon grandis
    No photo available

    Hydras

    Various species in the genus Hydra
    pink mucket

    Pink Mucket

    Lampsilis abrupta
    exclamation mark

    Endangered

    plain pocketbook

    Plain Pocketbook

    Lampsilis cardium
    Photo of a ramshorn snail on a wet rock.

    Ramshorn Snails

    Gyraulus, Helisoma, Menetus, Micromenetus, Planorbula spp.
    round pigtoe

    Round Pigtoe

    Pleurobema sintoxia
    Photograph of Sheepnose freshwater mussel shell exterior view

    Sheepnose (Bullhead)

    Plethobasus cyphyus
    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.
    wabash pigtoe

    Wabash Pigtoe

    Fusconaia flava
    Water springtails congregate in water above soggy dead leaves

    Water Springtail

    Podura aquatica