Field Guide

Aquatic Invertebrates

Showing 1 - 10 of 14 results
Media
Photo of a belted crayfish, also called Big River crayfish.
Species Types
Scientific Name
Faxonius harrisonii (formerly Orconectes harrisonii)
Description
The belted crayfish is medium-small, tan, with a distinctive pattern of alternating olive-green and reddish-brown bands on the abdominal segments. It is found only in the Big River and its tributaries.
Media
Photo of a freckled crayfish.
Species Types
Scientific Name
Cambarus maculatus
Description
The freckled crayfish is powerfully built, yellowish tan, with numerous conspicuous black spots on its pincers, carapace, and abdomen. It is largely restricted to the Courtois Hills section of the Meramec River basin.
Media
Photo of a golden crayfish viewed through the surface of creek water.
Species Types
Scientific Name
Faxonius luteus (formerly Orconectes luteus)
Description
The golden crayfish varies in color from olive green to golden yellow. Many body parts are trimmed with red. A dark band crosses the head just in front of the cervical groove, and another crosses the carapace at its junction with the abdomen. It's a wide-ranging species.
Media
Photo of a gray-speckled crayfish.
Species Types
Scientific Name
Faxonius palmeri (formerly Orconectes palmeri)
Description
The gray-speckled crayfish is gray with numerous greenish-black speckles and blotches. A pair of large blotches are present near the back of the head, and another pair occur where the carapace joins the abdomen. In Missouri, it is found only in the southeastern section.
Media
Photo of a longpincered crayfish.
Species Types
Scientific Name
Faxonius longidigitus (formerly Orconectes longidigitus)
Description
The longpincered crayfish is large and colorful, with very long, slender, blue-green pincers that are studded with prominent yellowish knobs. It is restricted to the White River basin in the Ozarks.
Media
Photo of a red swamp crawfish or crayfish.
Species Types
Scientific Name
Procambarus clarkii
Description
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.
Media
Photo of a ringed crayfish.
Species Types
Scientific Name
Faxonius neglectus (formerly Orconectes neglectus)
Description
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.
Media
Photo of a saddleback crayfish.
Species Types
Scientific Name
Faxonius medius (formerly Orconectes medius)
Description
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.
Media
Photo of a shield crayfish, also called a ditch fencing crayfish.
Species Types
Scientific Name
Faxonella clypeata
Description
The shield crayfish is small and tan, with a pattern of paired blackish dashes along the surface of the carapace and abdomen. The pincers are narrow, with short, abruptly tapering fingers. In Missouri it occurs only in our southeast counties.
Media
Photo of a spothanded crayfish viewed through creekwater.
Species Types
Scientific Name
Faxonius punctimanus (formerly Orconectes punctimanus)
Description
The spothanded crayfish is moderately large and usually has a noticeable black spot on each pincer near the base of the movable finger. In Missouri, it is found mostly in Ozark waterways in the southeastern quarter of the state, from Callaway, Montgomery, and Warren counties south.
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.