3 kinds · tap one for a closer look
Semi-aggressive.
342 species in our list are a good match.
Semi-aggressive. Should be kept alone or with sturdy fish and plenty of hides.
Check your local laws. EU: NOT on the Union list of invasive alien species (checked against the consolidated list of 7 Aug 2025, which includes Cherax destructor but not C. quadricarinatus); national rules may still apply. England and Wales: no licence needed to keep it in indoor aquaria for ornamental use (the only non-native crayfish with that exemption). US: Florida allows it only in commercial systems under an Aquaculture Certificate of Registration and Restricted Species Authorization; release of non-natives is illegal there. Other US state rules not checked. Check the rules where you live before you buy one, and never release it into the wild.
Good to know: Not on the EU invasive species list, but banned or restricted in some US states and other regions. Never release it into the wild.
Sinking pellets, vegetables and meaty foods.
Tap a food to see what it is.
Adult males have a bright red patch on the outer edge of the claws; females are smaller. Juveniles can be sexed by gonopore position: at the 5th walking legs in males and 3rd in females.
Common problems. Tap one to see the signs. This is a guide, not a diagnosis.
Egg-bearing mating pairs · Easy
The male places a spermatophore on the female; she attaches the fertilised eggs to her swimmerets and broods them for 6-10 weeks depending on temperature. Young hatch as miniature crayfish, stay attached for a few weeks and leave the mother 1-2 weeks after hatching. Breeds only above 23 °C; 3-5 broods per season.
One male and 2 females in a large tank with hides.
Large tank with caves and sand; separate female when berried.
Seasonal temperature changes and good feeding.
300-800 eggs per brood (up to about 1,000), brooded 6-10 weeks.
Juveniles are tiny crayfish; feed meaty foods and keep separate to prevent cannibalism.
A big, fast-growing tropical crayfish from northern Australia and New Guinea, farmed for food since the late 1980s and popular in aquariums in blue forms. Adults reach about 25 cm (up to 30 cm) and 500-600 g. Invasive where released in warm countries.
German zoologist Eduard von Martens described the red claw in 1868. It is a large tropical crayfish farmed in Australia and elsewhere, and its blue colours made it popular in big aquariums.
First described by Eduard von Martens in 1868. Named for 'Quadricarinatus' means four keels, after ridges on its head.
14 facts checked with sources
Invertebrate (Australian freshwater crayfish). Valid name. Sold as 'blue lobster' and 'tropical blue crayfish' too.
WoRMS / DecaNet (2026): Cherax quadricarinatus (AphiaID 885573, REST record)New value.
WoRMS / DecaNet (2026): Cherax quadricarinatus (AphiaID 885573, REST record)Total length. size-pick: 25 cm (about 250 mm) used; Queensland DPI (via Wikipedia) gives up to 30 cm and CABI (via USFWS) up to 35 cm, both maxima. Legacy 20 cm is below the adult maximum; farm harvest size is only 35-130 g, so many kept animals stay smaller.
USFWS Ecological Risk Screening Summary: Redclaw (Cherax quadricarinatus), rev. 2018 · Wikipedia: Cherax quadricarinatus (cites IUCN 2010, Queensland DPI&F)Legacy 22-30 °C matches 23-31 °C within about 1 °C. Breeds only above 23 °C.
FAO Cultured Aquatic Species Information Programme: Cherax quadricarinatusPond-water specification from FAO; legacy 7-8.5. FAO also says it tolerates 'wide daily pH changes'.
FAO Cultured Aquatic Species Information Programme: Cherax quadricarinatusNew value. >40 ppm (mg/L CaCO3) ÷ 17.85 = above 2.2 °dGH; no upper limit given.
FAO Cultured Aquatic Species Information Programme: Cherax quadricarinatusCABI via USFWS. Legacy 3-5 years.
USFWS Ecological Risk Screening Summary: Redclaw (Cherax quadricarinatus), rev. 2018FAO calls it 'physically robust' and tolerant of poor water quality, but gives no hobby rating.
FAO Cultured Aquatic Species Information Programme: Cherax quadricarinatusNew value. Also reported from Lake Balboa, Los Angeles, 2018-2019 (USFWS).
FAO Cultured Aquatic Species Information Programme: Cherax quadricarinatus · USFWS Ecological Risk Screening Summary: Redclaw (Cherax quadricarinatus), rev. 2018 · Wikipedia: Cherax quadricarinatus (cites IUCN 2010, Queensland DPI&F)Legacy red-patch sexing is correct.
FAO Cultured Aquatic Species Information Programme: Cherax quadricarinatus · Wikipedia: Cherax quadricarinatus (cites IUCN 2010, Queensland DPI&F)Legacy '100-500 eggs for about 6 weeks': duration fine, egg count too low (300-800).
FAO Cultured Aquatic Species Information Programme: Cherax quadricarinatus · Wikipedia: Cherax quadricarinatus (cites IUCN 2010, Queensland DPI&F)Legacy breeding.eggs only 'Females carry eggs under the tail'.
FAO Cultured Aquatic Species Information Programme: Cherax quadricarinatus · USFWS Ecological Risk Screening Summary: Redclaw (Cherax quadricarinatus), rev. 2018Legacy 'can reach 20 cm' corrected to about 25 cm (see adultSizeCm).
FAO Cultured Aquatic Species Information Programme: Cherax quadricarinatus · Wikipedia: Cherax quadricarinatus (cites IUCN 2010, Queensland DPI&F)IMPORTANT: the brief for this check said C. quadricarinatus is EU-listed; the EUR-Lex consolidated Annex (and the Wikipedia table) do not include it. Only C. destructor among Cherax was added (2025). Legacy 'Restricted or banned in parts of the USA' is partly confirmed (Florida). Note that the UK exemption applies to England and Wales (Wikipedia says not Scotland).
EUR-Lex: Commission Implementing Regulation (EU) 2016/1141 (Union list), consolidated text 7 Aug 2025 · EUR-Lex: Commission Implementing Regulation (EU) 2025/1422 of 17 July 2025 (third update of the Union list) · GOV.UK (Defra): Introduce or keep non-native fish, lobsters and crayfish (England and Wales; last updated 15 Oct 2026) · USFWS Ecological Risk Screening Summary: Redclaw (Cherax quadricarinatus), rev. 2018