Ringed Crayfish

Faxonius neglectus (formerly Orconectes neglectus)

ringed_crayfish.jpg

Photo of a ringed crayfish.
In Missouri, the ringed crayfish is found in clear, rocky Ozark streams in the southwestern quarter.
MDC Staff
Family

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

Description

This is a medium-sized olive-green to reddish-tan crayfish with prominent black or brown rings around the fingers of its pincers near the tips. The pincers are often very broad and heavy (especially in males) with a broad gap between the fingers when they are closed. A dark band crosses the carapace near its junction with the abdomen. A pair of dark stripes run lengthwise along the abdomen near its lateral (side) margins. No other crayfish within the range of this species has conspicuous black rings on the fingers.

Two subspecies occur in Missouri:

  • F. n. neglectus (the ringed crayfish), in the Spring (Neosho) River basin, is olive-green with orange pincer tips with a black ring.
  • F. n. chaenodactylus (the gap-ringed crayfish), in the North Fork and Bryant Creek drainages, is reddish-tan with broad brown rings on the pincer tips.
  • Populations in intervening streams of the White River basin show a mixture of the characteristics used to separate the two and are considered intergrades.

Similar species: The Ozark crayfish is often found in the same streams; it has about the same size and build but has numerous dark specks on the abdomen and pincers.

Size

Adult length: about 1½ to 3½ inches.

Habitat and conservation

Occurs in clear, rocky, permanent-flowing streams ranging in size from small creeks to large rivers. It occurs in rocky riffles and shallow pools having sufficient current to keep the bottom largely free of silt. This crayfish excavates cavities in gravel beneath large rocks. Where it occurs, it is the most abundant crayfish.

Foods

Forages at night on algae and detritus. Crayfish are generally omnivores, eating a wide variety of plant and animal materials.

image of Ringed Crayfish Distribution Map
Distribution in Missouri

Southwestern Ozark region of Missouri, from the North Fork of the White River in Howell County westward through the White and Spring (Neosho) River basins.

Life cycle

Breeding occurs from October to April and eggs are laid in the spring. Females carry eggs March through June, apparently peaking in April in warmer streams, but later in cooler, spring-fed streams. The young reach about 2 inches in length by the end of their first growing season. Most ringed crayfish live about 2½ years, though some can live as long as 5 years.

Human connections

In addition to feeding many types of wildlife, crayfish provide food for many species that humans hunt and fish. Crayfish commonly serve as fish bait, and many people eat crayfish, too. Crayfish are fascinating, colorful creatures in their own right, and part of our rich native heritage.

Ecosystem connections

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.