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 a belted crayfish, also called Big River crayfish.

    Belted Crayfish (Big River Crayfish)

    Faxonius harrisonii (formerly Orconectes harrisonii)
    Photo of a Big Creek crayfish.

    Big Creek Crayfish

    Faxonius peruncus (formerly Orconectes peruncus)
    Photo of a Cajun dwarf crayfish.

    Cajun Dwarf Crayfish

    Cambarellus puer
    Photo of a coldwater crayfish.

    Coldwater Crayfish

    Faxonius eupunctus (formerly Orconectes eupunctus)
    exclamation mark

    Endangered

    Photo of a spothanded crayfish viewed from above on white background.

    Crayfishes

    About 36 species in Missouri
    Photo of a digger crayfish.

    Digger Crayfish

    Creaserinus fodiens (formerly Fallicambarus fodiens)
    Photo of a longpincered crayfish.

    Longpincered Crayfish

    Faxonius longidigitus (formerly Orconectes longidigitus)
    Photo of a Mammoth Spring crayfish.

    Mammoth Spring Crayfish

    Faxonius marchandi (formerly Orconectes marchandi)
    Meek's Crayfish

    Meek’s Crayfish

    Faxonius meeki (formerly Orconectes meeki)
    Photo of a Neosho midget crayfish.

    Neosho Midget Crayfish

    Faxonius macrus (formerly Orconectes macrus)
    Photo of an Ozark crayfish.

    Ozark Crayfish

    Faxonius ozarkae (formerly Orconectes ozarkae)
    Photo of a red swamp crawfish or crayfish.

    Red Swamp Crawfish

    Procambarus clarkii
    Photo of a ringed crayfish.

    Ringed Crayfish

    Faxonius neglectus (formerly Orconectes neglectus)
    Photo of a saddleback crayfish.

    Saddleback Crayfish

    Faxonius medius (formerly Orconectes medius)
    Photo of amphipod on a rock

    Scuds and Sideswimmers (Amphipods)

    Species in the crustacean order Amphipoda
    Photo of a shrimp crayfish.

    Shrimp Crayfish

    Faxonius lancifer (formerly Orconectes lancifer)
    Photo of a spothanded crayfish viewed through creekwater.

    Spothanded Crayfish

    Faxonius punctimanus (formerly Orconectes punctimanus)
    Photo of a St. Francis River crayfish.

    St. Francis River Crayfish

    Faxonius quadruncus (formerly Orconectes quadruncus)
    Photo of a vernal crayfish.

    Vernal Crayfish

    Procambarus viaeviridus
    Photo of a northern, also called virile, crayfish.

    Virile Crayfish (Northern Crayfish)

    Faxonius virilis (formerly Oronectes virilis)
    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 White River crawfish.

    White River Crawfish

    Procambarus acutus
    Photo of Williams' crayfish.

    Williams’ Crayfish

    Faxonius williamsi (formerly Orconectes williamsi)
    Photo of a woodland crayfish.

    Woodland Crayfish

    Faxonius hylas (formerly Orconectes hylas)