Freckled Crayfish

Photo of a freckled crayfish.
Species of Conservation Concern
Scientific Name
Cambarus maculatus
Cambaridae (freshwater crayfish) in the order Decapoda (shrimp, crabs, and lobsters)

The freckled crayfish is a powerfully built, yellowish-tan crayfish with numerous conspicuous black spots on its pincers, carapace, and abdomen. It is distinguished from all other species within its limited range by the pattern of conspicuous black spots over the entire dorsal (top) surface. As with many Ozark crayfish, the river system it occurs in is a big clue for identification.


Adult length: about 2 to 3¼ inches.

Where To Find
Freckled Crayfish Distribution Map

This crayfish occurs only in the Meramec River basin of the Missouri Ozarks, especially the eastern and central areas of the basin, the Courtois Hills.

The freckled crayfish lives in the very clear, high-gradient, spring-fed streams and small rivers of the Meramec Basin. Rarely seen in the open, it digs burrows in gravel beneath large rocks and stays there, probably emerging at night to feed. Where it occurs, it is not as abundant as the other crayfish that live in the same streams.

Crayfish are generally omnivores, eating a wide variety of plant and animal materials.

The freckled crayfish has a very limited range within Missouri and occurs nowhere else in the world (it is endemic to our state). It is a Missouri species of conservation concern, and it is vulnerable to extinction. It was first described scientifically as a new species in 1988.

Life Cycle

Mating probably occurs in the fall, and females have been observed carrying eggs in May. Apparently they carry eggs about a month later than do female spothanded, golden, and saddlebacked crayfish, which often occur in the same areas. Freckled crayfish apparently can live to about 4 years of age.

Crayfish are eaten by many types of wildlife, including species that humans hunt and fish. Crayfish are fascinating, colorful creatures and are part of our rich native heritage.

Species of conservation concern, such as this one, are protected from harvest by state law.

Crayfish are an important link in the food chain between plants and other animals, breaking down plant materials that are resistant to decay. Crayfish in turn are an important food for many other animals.

Presence of crayfish in a stream or pond usually indicates good water quality.

Media Gallery
Similar Species
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.