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)
    Photo of a spothanded crayfish viewed from above on white background.

    Crayfishes

    About 36 species in Missouri
    elktoe

    Elktoe

    Alasmidonta marginata
    fatmucket

    Fatmucket

    Lampsilis siliquoidea
    Photo of a fishfly larva crawling among rocks in an aquarium.

    Fishfly Larvae

    Chauliodes, Neohermes, and Nigronia spp. (in eastern US)
    Monkey Face Mussel

    Freshwater Mussels

    Bivalve molluscs in order Unionoida
    giant floater

    Giant Floater

    Pygandon grandis
    Photo of a leech

    Leeches

    Various species in the subclass Hirudinea
    pimpleback

    Pimpleback

    Quadrula pustulosa
    plain pocketbook

    Plain Pocketbook

    Lampsilis cardium
    Photograph of Purple Wartyback freshwater mussel shell exterior view
    round pigtoe

    Round Pigtoe

    Pleurobema sintoxia
    Photo of a pink planarian on a rock.

    Turbellarians (Planarians; Free-Living Flatworms)

    Species in genera Dugesia, Planaria, etc.
    Photo of a northern, also called virile, crayfish.

    Virile Crayfish (Northern Crayfish)

    Faxonius virilis (formerly Oronectes virilis)
    wabash pigtoe

    Wabash Pigtoe

    Fusconaia flava