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

    Bryozoans (Moss Animals)

    Freshwater species in the phylum Bryozoa
    Photo of a spothanded crayfish viewed from above on white background.

    Crayfishes

    About 36 species in Missouri
    Monkey Face Mussel

    Freshwater Mussels

    Bivalve molluscs in order Unionoida
    Image of a giant red-headed centipede.

    Giant Red-Headed Centipede

    Scolopendra heros
    Venomous Icon

    Venomous

    Photo of a leech

    Leeches

    Various species in the subclass Hirudinea
    Narceus Millipede crawling across gravel

    Millipedes

    More than 900 species in North America north of Mexico
    A reddish centipede crawls over a rock

    Soil Centipedes

    Estimated 4,000 species globally
    Photo of a pink planarian on a rock.

    Turbellarians (Planarians; Free-Living Flatworms)

    Species in genera Dugesia, Planaria, etc.
    image of Xystodesmid Millipede crawling on a forest floor

    Xystodesmid Millipedes

    8 tribes, with about 23 genera, in North America north of Mexico