Coldwater Crayfish

Faxonius eupunctus (formerly Orconectes eupunctus)

coldwater_crayfish.jpg

Photo of a coldwater crayfish.
The coldwater crayfish has a very localized distribution in the Eleven Point and Spring River drainages. It is an imperiled species.
Chris Lukhaup
Species of Conservation Concern
Family

Cambaridae (freshwater crayfish), in the order Decapoda (shrimp, crabs, and lobsters)

Description

The coldwater crayfish is a medium-small, stout crayfish with a blue-green head and pincers and a dark rust-brown carapace. The abdomen has a pair of conspicuous white lateral spots on the first segment, and a tapering V-shaped dark central stripe. This crayfish is distinguished from other crayfish within its range by the distinctive red and green color and V-shaped central stripe on the abdomen.

Size

Adult length: about 1¼ to 2¾ inches.

Habitat and conservation

In the Eleven Point River and Greer Spring Branch, this is the most abundant crayfish. It occurs over coarse gravel and rock substrate in swift, shallow water. It is often found beneath rocks, in cavities that it excavates in gravel and sand.

Foods

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

image of Coldwater Crayfish Distribution Map
Distribution in Missouri

The coldwater crayfish has a very localized distribution in the Eleven Point River and Spring River drainages of the Ozark Region in southern Missouri and Arkansas.

Status

Imperiled; a Species of Conservation Concern. This species is rare and only found in a small range, so it is vulnerable to extirpation. The Eleven Point River and Spring River are clear and cold and are fed by two of the largest Ozark springs (Greer and Mammoth). This is the most abundant crayfish in the Eleven Point River (downstream of Greer Spring), but it does not live in its tributaries.

Life cycle

Mating occurs in the fall, beginning in mid-September and probably extending into November, and females carry eggs between March and May. Some become sexually mature by the end of their first year, but most reach maturity during their second year. The normal life span seems to be about two and a half years.

Human connections

Crayfish feed many types of wildlife, including many species that humans hunt and fish. Crayfish commonly serve as bait, plus many people eat crayfish, too. Crayfish are fascinating, colorful creatures in their own right and are part of our rich natural heritage.

Ecosystem connections

Their opportunistic, omnivorous feeding makes crayfish an important link in the food chain between plants and vertebrates, breaking down plant and other materials that are resistant to decomposition. Crayfish in turn are an important food for many other animals.