Cambarus cracens

Slenderclaw Crayfish

FWS Focus

Overview

Characteristics
Overview

The slenderclaw crayfish is a relatively small freshwater crustacean that is endemic to streams within the Tennessee River Basin in DeKalb and Marshall counties, Alabama.

Scientific Name

Cambarus cracens
Common Name
Slenderclaw Crayfish
FWS Category
Crustaceans
Kingdom

Location in Taxonomic Tree

Identification Numbers

TSN:

Characteristics

Characteristic category

Habitat

Characteristics
Habitat

The crayfish occurs in small to medium flowing streams with intact native vegetation on the stream banks, with boulder and cobble substrates. In addition, the species needs abundant space within each habitat type for sheltering and adequate seasonal water flows to maintain connectivity of streams.   

River or Stream
Characteristic category

Life Cycle

Characteristics
Reproduction

Adult slenderclaw crayfish have two forms:

  • Form I: Reproductively active or breeding
  • Form II: Reproductively inactive, or non-breeding.

Sexual maturity is believed to be reached by year one.

Life Span

Very little is known of the biology and life history of the slenderclaw crayfish. Based on information we know of other crayfish species, the life span is likely to be 2 to 3 years.

Life Cycle

Very little is known of the biology and life history of the slenderclaw crayfish. Based on information slenderclaw crayfish collections and what we know of other crayfish species, the species has four identified life stages: fertilized eggs, juveniles, nonbreeding adults and breeding adults.

Characteristic category

Physical Characteristics

Characteristics
Physical Characteristics

This species is a cryptic, stream-dwelling crayfish. It lives in the open stream and takes shelter by crawling and burrowing under rocks and logs.

Size & Shape

The slenderclaw crayfish is a relatively small, freshwater crustacean with a comparatively elongate, slender front claw. The largest individual documented was 1.56 inches (carapace length).

Color & Pattern

Two color variations have been documented. The first being mostly uniform olive green to rusty brown and the second being a distinct mottled pattern with light gray to straw coloring with speckling of rusty red to dark brown.

Characteristic category

Behavior

Characteristics
Behavior

This species is a cryptic, stream-dwelling crayfish and is lives in the open stream and takes shelter by burrowing under rocks

Geography

Characteristics
Geography

Based on the best available  information from other crayfishes, slenderclaw crayfish likely eat aquatic macroinvertebrates in the juvenile stage and shift toward eating both plant and animals in the adult stage. 

Range

The slenderclaw crayfish is native to Sand Mountain in the Southwestern Appalachian Ecoregion, on the Cumberland Plateau in the Tennessee River Basin. It is found in Alabama in tributaries on the south side of Guntersville Lake on the Tennessee River. The slenderclaw crayfish occurs in Shoal Creek and Town Creek watersheds on Sand Mountain. 

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Timeline

Explore the information available for this taxon's timeline. You can select an event on the timeline to view more information, or cycle through the content available in the carousel below.

7 Items

Listing

Listing

Critical Habitat

4d

Listing

Critical Habitat

Listing

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Listing

Sep 27, 2011

Sep 27, 2011 Listing (Substantial)
Partial 90-Day Finding on a Petition To List 404 Species in the Southeastern United States as Endang…
  • Publication type: 90 day petition finding
  • Population:
Item 1

Listing

Oct 9, 2018

Oct 9, 2018 Listing (Warranted)
Threatened Species Status With Section 4(d) Rule and Critical Habitat Designation for Slenderclaw Cr…
  • Publication type: 12m petition finding
  • Population:
Item 2

Critical Habitat

Oct 9, 2018

Oct 9, 2018 Critical Habitat
Threatened Species Status With Section 4(d) Rule and Critical Habitat Designation for Slenderclaw Cr…
  • Publication type: Proposed
  • Population:
Item 3

4d

Oct 9, 2018

Oct 9, 2018 4d
Threatened Species Status With Section 4(d) Rule and Critical Habitat Designation for Slenderclaw Cr…
  • Publication type: Proposed
  • Population:
Item 4

Listing

Oct 9, 2018

Oct 9, 2018 Listing (Threatened)
Threatened Species Status With Section 4(d) Rule and Critical Habitat Designation for Slenderclaw Cr…
  • Publication type: Proposed
  • Population:
Item 5

Critical Habitat

Sep 8, 2021

Sep 8, 2021 Critical Habitat
Endangered and Threatened Species: Endangered Species Status for Slenderclaw Crayfish and Designatio…
  • Publication type: Final
  • Population:
Item 6

Listing

Sep 8, 2021

Sep 8, 2021 Listing (Endangered)
Endangered and Threatened Species: Endangered Species Status for Slenderclaw Crayfish and Designatio…
  • Publication type: Final
  • Population:
Item 7