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Image of Red swamp crawfish
Unresolved name

Red Swamp Crawfish

Procambarus clarkii

Diagnostic Description

provided by FAO species catalogs
Body shape cylindrical.

Cephalotorax conspicuously granular (roughened) in adults, provided of numerous small tuberculi and also having strong cervical, cephalic, branchiostegal, and marginal spines. Rostrum long with margins straight, convergent, having marginal spines near its tip, ending in a triangular acumen. Chelae narrow and long, notch in proximal portion of dactyl, leaving gap and delimited by tubercle. Large tubercle opposite end of gap on fixed finger; large scarlet tubercles on the palm and fingers. Carapace not separated at the middle (dorsally) by a space, the areola.

Colour in adults dark red, some in shades of brown. A wedge-shaped black stripe is present on the abdomen. Chelae with bright red tubercles. Juveniles uniform grey, sometimes overlain by dark wavy lines.

Size

provided by FAO species catalogs
Total lenght usually between 10,5-11,8 cm (35 to 56 g wet weight respectively). Maximum size up to 20 cm.

Brief Summary

provided by FAO species catalogs
In lentic and lotic freswater habitats: sluggish streams and lentic habitats, swamps, ditches, sloughs, ponds, etc. especially in vegetation, leaf litter, etc. It avoids streams and ditches with strong flow, where it is replaced by other species (i.e. the White River crayfish Procambarus acutus).Territorial behaviour, aggressive with its own species. It burrows during periods of drought or cold.A benthic omnivorous, feeding on insects, larvae, detritus, etc. with preference for vegetal matter. Females fecundity around 500 eggs average. Females dig burrows in dry areas in the period of reproduction (late spring- early summer in the area of origin). It is a fast-growing species: in adequate conditions larvae were born after 21 days of incubation (5 mm long at 2 days), growing to 2 cm 1 month later and up to 80 mm of lenght in 3 months.

An eurytermal species (10-22 °C to 30 °C or more). Inhabit all types of water, with preference for hard water.

Benefits

provided by FAO species catalogs
P. clarkii is the dominant North American commercial crayfish. Wild P. clarkii caught seasonally using fishing traps. There is an important aquaculture industry for crayfish in the USA. Culture is developed on farm ponds. Most commercial exploitation of the red swamp crayfish, and the related species Procambarus zonangulus, occurs in Louisiana. Statistics from 1984-1986 oscillated between 27 000 to 44 318 tonnes/yr. (between ca. 30000-45000 tons/yr in Lousiana in recent years - 85% of catches of P. clarkii). In the areas where it has been introduced P. clarkii is highly invasive and a potential vector for the crayfish plague (the fungi Aphanomyces astaci). Crayfish plague was introduced into Europe in 1960s with massive introduction of American freshwater crayfish species. Ever since, many native freshwater crayfish populations disminished or it have been eliminated. Crayfish are economically important in a number of the USA states for human consumption and also as fish bait.