Photo of an aquatic isopod in an aquarium, crawling on a rock.

    Aquatic Pillbugs and Sowbugs (Aquatic Isopods)

    Freshwater members of the crustacean order Isopoda
    Photo of eyed click beetle on bark

    Click Beetles

    Approximately 1,000 species in North America
    Photo of a freshwater jellyfish

    Freshwater Jellyfish

    Craspedacusta sowerbii (syn. C. sowerbyi)
    Photo of several prosobranch pond snails crawling on a rock.

    Gilled Aquatic Snails (Prosobranch Pond Snails)

    Over 20 Missouri species in former subclass Prosobranchia
    No photo available

    Hydras

    Various species in the genus Hydra
    image of an Ichneumon Wasp on tree trunk

    Ichneumon Wasps

    More than 5,000 species in North America

    Land Snails and Slugs

    Approx. 150 species of land snails and slugs in Missouri
    Swamp milkweed leaf beetle on a leaf it has chewed on.

    Leaf Beetles

    About 2,000 species in North America
    image of a Leafhopper on leaf

    Leafhoppers

    More than 3,000 species in North America north of Mexico
    Red milkweed beetle eating a common milkweed leaf.

    Longhorned Beetles (Borers; Sawyer Beetles)

    About 1,000 species in North America north of Mexico
    Male eastern Hercules beetle walking in grass

    Scarab Beetles

    About 1,700 species in North America north of Mexico.
    Photo of amphipod on a rock

    Scuds and Sideswimmers (Amphipods)

    Species in the crustacean order Amphipoda
    Photo of a firebrat, a type of silverfish

    Silverfish (Firebrat)

    Lepisma saccharina, Thermobia domestica, and other species
    Photo of a pink planarian on a rock.

    Turbellarians (Planarians; Free-Living Flatworms)

    Species in genera Dugesia, Planaria, etc.
    Zebra Mussel

    Zebra Mussel

    Dreissena polymorpha
    invasive icon

    Invasive