Content tagged with "Aquatic Invertebrates"

Photo of a predaceous diving beetle

Predaceous Diving Beetles (Water Tigers)

Species in the beetle family Dytiscidae
Like many aquatic insects, these large oval beetles prey voraciously on other aquatic organisms. Excellent swimmers, they fly well, too, and are often attracted to lights.

Read more

Photograph of Purple Wartyback freshwater mussel shell exterior view

Purple Wartyback (Purple Pimpleback)

Cyclonaias tuberculata
Before buttons were made of plastic, they were made of shell. Because only white buttons were in demand, the coppery-purple shell of this species made it worthless for the button industry.

Read more

Ramshorn Snails (Wheel Snails; Planorbids)

Gyraulus, Helisoma, Menetus, Micromenetus, Planorbula spp.
This group of freshwater snails is easy to identify at a glance, because the shell is a flat, disklike coil. Like other pulmonate snails, they lack an operculum (a hard horny “trapdoor” that other types of aquatic snails possess that closes when the animal retracts into the shell).

Read more

Photo of a red swamp crawfish or crayfish.

Red Swamp Crawfish (Red Swamp Crayfish)

Procambarus clarkii
Adult red swamp crawfish are dark red (nearly black on the carapace) and have a wedge-shaped black stripe on the abdomen. Juveniles are a uniform gray, sometimes overlain by dark wavy lines. In Missouri it lives in the Bootheel.

Read more

Photo of a ringed crayfish.

Ringed Crayfish

Orconectes neglectus
The ringed crayfish is olive green to reddish tan and usually has black or brown rings around the pincer tips. In Missouri it is found in clear, rocky Ozark streams in the southwestern quarter.

Read more

round pigtoe

Round Pigtoe

Pleurobema sintoxia
Round pigtoes are more rounded than Wabash pigtoes. Usually, the nacre (the shell lining) is white, but in rare individuals it is bright pink.

Read more

Photo of a saddleback crayfish.

Saddleback Crayfish (Saddlebacked Crayfish)

Orconectes medius
The saddleback crayfish has a bold blackish band across the hind margin of the carapace and lacks dark blotches or specks. The pincers are broad and powerful. It occurs in the Big and Meramec river drainages.

Read more

Photo of a Salem cave crayfish.

Salem Cave Crayfish

Cambarus hubrichti
The Salem cave crayfish has a special habitat: It lives in caves in the Missouri Ozarks. Its localized distribution makes its populations vulnerable to catastrophes that might pollute or damage their cave environment.

Read more



Leptodea leptodon
Rarely seen, this Endangered freshwater mussel has a thin and delicate shell that is strikingly beautiful inside.

Read more

Photo of an amphipod, or scud, on a rock.

Scuds (Amphipods)

Species in the crustacean order Amphipoda
Often overlooked by people, but eagerly sought by fish, Missouri’s amphipods could be described as “shrimplike sowbugs.” Scuds live in various aquatic habitats, and several species inhabit caves.

Read more