Photo of a leech

    Leeches

    Various species in the subclass Hirudinea
    Photo of an aquatic tubificid worm among rocks in an aquarium.

    Tubificid Worms (Tubifex Worms)

    Tubifex spp. and other aquatic tubificid annelids
    Water springtails congregate in water above soggy dead leaves

    Water Springtail

    Podura aquatica