Field Guide

Aquatic Invertebrates

Showing 1 - 10 of 39 results
Media
Photo of a pink planarian on a rock.
Species Types
Scientific Name
Dugesia, Planaria, and other genera
Description
Unlike their parasitic cousins in the flatworm group, turbellarians, or planarians, are tiny carnivores or detritus-eaters that glide smoothly across submerged leaves and other objects.
Media
Gray, speckled, translucent gelatinous blob cut in half to show structure
Species Types
Scientific Name
Freshwater species in the phylum Bryozoa
Description
Bryozoans are tiny, filter-feeding invertebrates. They create colonies that can be mossy, branching, or round and jellylike.
Media
Photo of hellgrammite
Species Types
Scientific Name
Corydalus cornutus
Description
Hellgrammites are the aquatic larval form of eastern dobsonflies. They are fiercely predaceous and look a little like centipedes. Anglers often use them as bait.
Media
Photo of a horsehair worm in an aquarium
Species Types
Scientific Name
About 350 species scientifically described.
Description
Adult horsehair worms can be nearly 3 feet long and live in water. They are practically featureless, smooth, aquatic worms that writhe into knots and curls.
Media
Photo of a painted devil crayfish standing on a sandy substrate
Species Types
Scientific Name
Lacunicambarus ludovicianus (syn. Cambarus ludovicianus)
Description
The painted devil crayfish is a burrowing lowland species. In Missouri, it is known from only a few locations in the Bootheel. Its overall color is olive green to blue, with reddish and cream markings.
Media
Photo of a paintedhand mudbug carefully arranged against a black background
Species Types
Scientific Name
Lacunicambarus polychromatus (syn. Cambarus polychromatus)
Description
The paintedhand mudbug is a burrowing crayfish known in Missouri from only a few locations along the eastern border of the Bootheel. It is tan to olive green, and the abdominal segments and tail fan are trimmed with red. The pincers have red spots and red tips.
Media
Photo of a devil crayfish.
Species Types
Scientific Name
Lacunicambarus aff. diogenes (syn. Cambarus diogenes)
Description
The powerfully built devil crayfish is usually a uniform olive or tan, without obvious blotches or spots. It digs underground burrows, often with mud chimneys, and has a wide distribution.
Media
Photo of a shrimp crayfish.
Species Types
Scientific Name
Faxonius lancifer (formerly Orconectes lancifer)
Description
The shrimp crayfish is medium-small, light reddish brown to gray, and thickly dusted with darker specks. Its noselike rostrum is unusually long, with the tip longer than the base, and the pincers are narrow and weak. It is found in the Bootheel.
Media
Bluefer
Species Types
Scientific Name
Potamilus purpuratus
Description
Like the pink heelsplitter and fragile and pink papershells, the bluefer uses freshwater drum as a host.
Media
pink mucket
Species Types
Scientific Name
Lampsilis abrupta
Description
This endangered native mussel lives in flowing waters of large streams among gravel and cobble.
See Also

About Aquatic Invertebrates in Missouri

Missouri's streams, lakes, and other aquatic habitats hold thousands of kinds of invertebrates — worms, freshwater mussels, snails, crayfish, insects, and other animals without backbones. These creatures are vital links in the aquatic food chain, and their presence and numbers tell us a lot about water quality.