Cherax quadricarinatus

Cherax quadricarinatus
Conservation status
Least Concern (IUCN 3.1)
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Subphylum:	Crustacea
Class:	Malacostraca
Order:	Decapoda
Family:	Parastacidae
Genus:	Cherax
Species:	C. quadricarinatus
Binomial name
Cherax quadricarinatus (Von Martens, 1868)

Cherax quadricarinatus (known by several common names, including Australian red claw crayfish, Queensland red claw, redclaw, tropical blue crayfish, yabby and freshwater blueclaw crayfish) is an Australian freshwater crayfish.

Distribution and ecology

C. quadricarinatus is found in permanent freshwater streams, billabongs and lakes on the north coast of the Northern Territory and northeastern Queensland.^[1] Populations are also found in Papua New Guinea. Through translocation by humans, the range has spread down to southern Queensland and into the far north of West Australia. C. quadricarinatus is considered an invasive species, and has established feral populations in South Africa, Mexico, Jamaica and Puerto Rico.^[1]

This tropical crustacean is very tolerant of environmental changes, and is primarily a detritivore.

Description

The colour of C. quadricarinatus ranges from dark brown to blue-green and adult males have a distinct red patch on the outer margin of the claws.^[2] They can reach up to 600 grams (21 oz).^[2]

Life cycle

Females, which are smaller than males, spawn 300–800 olive-green eggs per brood,^[3] which are fertilised from a spermatophore which the male has deposited at the base of her walking legs (pereiopods) during mating. Fertilised eggs are affixed to the female's pleopods, situated on the underside of the tail. Incubation takes approximately six weeks and the newly hatched juveniles rapidly become independent.^[3]

Aquaculture

C. quadricarinatus is farmed commercially in Queensland and the Northern Territory, and is harvested at between 35–130 grams (1.2–4.6 oz).^[3] C. quadricarinatus is a sought-after product with a delicate crustacean flavour. They are both non-aggressive in nature and highly fertile, and can therefore be bred in large numbers in captivity. Time to sexual maturity, and therefore harvest size, is somewhere between six to twelve months in optimal farmed conditions.

References

1. ^ ^{a b} C. M. Austin, C. Jones & M. Wingfield (2009). "Cherax quadricarinatus". IUCN Red List of Threatened Species. Version 2009.2. International Union for Conservation of Nature. http://www.iucnredlist.org/apps/redlist/details/4621. Retrieved October 4, 2010. 
2. ^ ^{a b} Brendan Johnson (June 10, 2010). "Redclaw (Primary Industry & Fisheries, Queensland)". Department of Employment, Economic Development and Innovation, Government of Queensland. http://www.dpi.qld.gov.au/28_14696.htm. Retrieved October 4, 2010. 
3. ^ ^{a b c} John Dexter (APril 8, 2009). "Redclaw (Primary Industry & Fisheries, Queensland)". Department of Employment, Economic Development and Innovation, Government of Queensland. http://www.dpi.qld.gov.au/28_13348.htm. Retrieved October 4, 2010. 

External links

• Freshwater crayfish (Redclaw) fisheries information