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
    Photo of a male Banded Pennant dragonfly

    Dragonflies

    Species in the suborder Anisoptera
    elktoe

    Elktoe

    Alasmidonta marginata
    image of a Summer Fishfly

    Fishflies

    Chauliodes, Neohermes, and Nigronia spp. (in eastern US)
    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
    Photo of a leech

    Leeches

    Various species in the subclass Hirudinea
    image of Narceus Millipede crawling across gravel

    Millipedes

    More than 900 species in North America north of Mexico
    image of a Carolina Grasshopper

    Short-Horned Grasshoppers

    About 620 species in North America
    Photo of a pink planarian on a rock.

    Turbellarians (Planarians; Free-Living Flatworms)

    Species in genera Dugesia, Planaria, etc.