Procambarus Versutus
Common Name: SLY CRAYFISH
Scientific Name: Procambarus (Pennides) versutus (Hagen)
Origin: USA
Max body size: 7cm
Keeping: You can keep one pair in an aquarium of 60cmx30cm. Bigger tanks allow for a greater number of individuals. A wide range of pH and GH is possible as long as one avoids the extremes. Quite tolerant to a wide range of water conditions and quality.
Behaviour: like most crayfish these are omnivorous. However they are no great eaters and keeping them in a planted tank is possible, as long as one does not need a perfect tank and can live with the little damage they do.Intra-species aggression is not big, one can even raise most of the young ones in the adults' tank.
How to tell apart males from females: As usual (longer pincers, gonopods in males, broader tail in females)
Breeding: as usual
spread: rare
remark: get blue most easily. Does have something to do with diet I think. Color can change from brown to blue and back after each molt.
Rarity Ranks: G5/S1
State Legal Status: Rare
Federal Legal Status: None
Description: The Sly Crayfish is dorsally tan or brown with cream and black markings. Striking cream-colored stripes run horizontally along the sides of the carapace and abdomen. The rostrum bears spines lateral to the tip and has a central ridge (carina). There are two distinctive cervical spines on either side of the carapace. The claws are dark, but the tubercles on the claws are even darker. The abdomen is brown and is covered with black blotches; these black markings form a horizontal band with irregular edges along the sides of the abdomen. The areola is 2-3 times as long as broad and comprises 24 - 28 percent of the total length of the carapace. Males of this species may reach a maximum total body length of over 90 mm (3.5 in). Mature females are about the same size, but males have notably larger claws.
Similar Species: The Sly Crayfish has a distinctive color pattern in life that makes it easy to distinguish from other crayfishes within in its range. However, it may be difficult to distinguish from preserved specimens of the White Tubercled Crayfish (Procambarus spiculifer). The dark (vs. white) tubercles of the sly crayfish are a helpful character.
Habitat: The Sly Crayfish has been found only in clear, free-flowing streams. During the day they are usually found within debris, aquatic plants (e.g., Golden Club, Orontium aquaticum), and washed out root masses along the banks of sand-bottomed streams. They move out over the sand to forage at night. They may dig simple burrows into the banks of streams. This species is usually found in low pH (acidic) streams, whereas the White Tubercled Crayfish is usually found in streams of near neutral pH. High quality habitat for the Sly Crayfish occurs in Pine Knot Creek and other eastern tributaries of Upatoi Creek.
Diet: No studies of the Sly Crayfish diet are known. Crayfishes are considered opportunistic omnivores and likely feed on live and decaying vegetation, aquatic insect larvae, small fishes, and dead animal matter.
Life History: The only life history information published is notes provided by Hobbs (1981). Hobbs (1981) examined only five specimens from Georgia, but in Alabama and Florida he reported males in reproductive condition from all months of the year and egg-bearing females from April to June. Stanton (2006) also collected males in reproductive condition throughout the year in Georgia, but rarely encountered egg-bearing females.
Survey Recommendations: Disturbing the substrate around aquatic plants and debris upstream from a net is productive. Because crayfish are typically more active at night, trapping may also be effective.
Range: The Sly Crayfish is distributed within the Chattahoochee River system in Chattahoochee and Marion counties. With the exception of a few small creeks draining directly into the Chattahoochee River from Fort Benning, Georgia, records of the Sly Crayfish are restricted to the Upatoi Creek system. This species is also found in creeks across southern Alabama and in the panhandle of Florida.
Threats: The Sly Crayfish is threatened in Georgia by its small geographic range and land uses within that range. The Chattahoochee County habitat lies within federal property, the Fort Benning Military Reservation. This habitat has been well protected in the past, but could be threatened by increased military training occurring on base. Two of the best Marion County localities have been impacted by recent highway construction.
Conservation and Management Recommendations: Conserving populations of the Sly Crayfish will require general watershed-level conservation practices, such as protection of riparian zones and adherence to best management practices for forestry, agriculture, and highway construction. Special efforts should be made to protect important populations in Black, Juniper, and Pine Knot Creeks and Fort Benning should include this species in future conservation planning efforts. Non-native crayfishes should never be used for bait. Instead, anglers should use crayfishes collected from the river system they will be fishing in and should never release unused bait crayfish back into Georgia waters.
Selected References:
Bouchard, R. W. 1976. Crayfishes and shrimps. In: H. Boschung, ed., Endangered and Threatened Plants and Animals of Alabama. Bulletin of the Alabama Museum of Natural History 2:13-20. Page 14.
Hagen, H. A. 1870. Monograph of the North American Astacidae. Illustrated Catalogue of the Museum of Comparative Zoology at Harvard College 3:117 p.
Hobbs, H. H., Jr. 1981. The crayfishes of Georgia, Smithsonian Contributions to Zoology 318:1–549.
Stanton, G. E. 2006. Evaluation of conservation status of six West Georgia, Chattahoochee-Flint River crayfish species. Report to the Georgia Department of Natural Resources, Georgia Natural Heritage Program, Social Circle, GA. 60 p.
Taylor, C. A., G. A. Schuster, J. E. Cooper, R. J. DiStefano, A. G. Eversole, P. Hamr, H. H. Hobbs III, H. W. Robison, C. E. Skelton, and R. F. Thoma, 2007. A reassessment of the conservation status of crayfishes of the United States and Canada after 10+ years of increased awareness. Fisheries 32(8):372-389.
Author of species account: George E. Stanton
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