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
    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 hellgrammite

    Hellgrammite

    Corydalus cornutus
    Photo of a leech

    Leeches

    Various species in the subclass Hirudinea
    Photo of a pink planarian on a rock.

    Turbellarians (Planarians; Free-Living Flatworms)

    Species in genera Dugesia, Planaria, etc.
    Photo of a water nymph crayfish, side view of specimen carefully arranged against black background

    Water Nymph Crayfish

    Faxonius nais (formerly Orconectes nais)
    Photo of a water scorpion, genus Ranatra, captured in a jar of pond water.

    Water Scorpions

    Ranatra spp. and Nepa apiculata