Fabio Pupin / Red swamp crayfish (Procambarus clarcki), invasive species, captive, Italy, July.

Remi Masson / European crayfish (Astacus astacus) in a lake. Alps, Switzerland, July.

Linda Pitkin / 2020VISION / White clawed crayfish (Austropotamobius pallipes) on river bed, viewed underwater, River Leith, Cumbria, England, UK, September 2012.

Linda Pitkin / 2020VISION / White clawed crayfish (Austropotamobius pallipes) underwater on riverbed, showing defensive posture, River Leith, Cumbria, England, UK, September 2012. Did you know? White clawed crayfish can live fo...

Linda Pitkin / 2020VISION / White clawed crayfish (Austropotamobius pallipes) underwater on riverbed, River Leith, Cumbria, England, UK, September 2012.

Konrad Wothe / Australian Red Claw Crayfish (Cherax quadricarinatus), Daintree National Park, North Queensland, Queensland, Australia

Paul Hobson / Signal Crayfish {Pacifastacus leniusculus} Leicestershire, UK

Georgette Douwma / Painted spiny lobster (Palinurus versicolor) juvenile. West Papua, Indonesia. Indo-West Pacific.

Paul Hobson / Signal crayfish (Pacifastacus leniusculus) displaying aggression with claws up. River Don, Sheffield, England, UK. September 2018.

Paul Hobson / White-clawed crayfish (Austropotamobius pallipes) on riverbed, split level image. Staffordshire, England, UK. October.

David Fleetham / California spiny lobster (Panulirus interruptus) on sea floor. Santa Barbara Island, California, USA.

Remi Masson / Signal crayfish (Pacifastacus leniusculus) in a river. Haute-Savoie, Alps, France, October.

Remi Masson / Stone crayfish (Austropotamobius torrentium) in a small river. There are only 3 populations of this species left in France. Haute-Savoie, Alps, France, July.

Remi Masson / Signal crayfish (Pacifastacus leniusculus) in a river. Alps, Haute-Savoie, France. October. Invasive species.

Remi Masson / Louisiana crayfish (Procambarus clarkii) in a river. Alps, Savoie, France. Invasive species.

Jan Hamrsky / European crayfish (Astacus astacus), underwater, August, Europe, controlled conditions

Jan Hamrsky / European crayfish (Astacus astacus), underwater, August, Europe, controlled conditions

Jan Hamrsky / European crayfish (Astacus astacus), August, Europe, controlled conditions

Jan Hamrsky / European crayfish (Astacus astacus), underwater, August, Europe, controlled conditions

Michael Durham / Coastal Giant Salamander (Dicamptodon tenebrosus), neotenic individual, swallowing Signal Crayfish (Pacifastacus leniusculus), Columbia River Gorge, Oregon

Alex Mustard / Four California spiny lobsters (Panulirus interruptus) shelter beneath a boulder in a kelp forest. Santa Barbara Island, Channel Islands. Los Angeles, California, United States of America. North East...

Franco Banfi / North American crayfish (Orconectes limosus) pair mating, Lake Lugano, Ticino, Switzerland, November.

Franco Banfi / North American crayfish (Orconectes limosus) pair mating, Lake Lugano, Ticino, Switzerland

Franco Banfi / North American crayfish (Orconectes limosus), Lake Lugano, Ticino, Switzerland, November.

Franco Banfi / North American crayfish (Orconectes limosus), Lake Lugano, Ticino, Switzerland, November.

Franco Banfi / North American crayfish (Orconectes limosus), Lake Lugano, Ticino, Switzerland

Franco Banfi / North American crayfish (Orconectes limosus) pair mating, Lake Lugano, Ticino, Switzerland, November.

Franco Banfi / North American crayfish (Orconectes limosus), Lake Lugano, Ticino, Switzerland

Richard Robinson / New Zealand crayfish or southern rock lobster (Jasus edwardsii) hides under the yellow zoathhid anemone (Parazoanthus elongates) in Doubtful Sound, Fiordland National Park, New Zealand.

Richard Robinson / New Zealand crayfish or southern rock lobster (Jasus edwardsii) in Doubtful Sound, Fiordland National Park, New Zealand.

Richard Robinson / New Zealand crayfish or southern rock lobster (Jasus edwardsii) in Dusky Sound, Fiordland National Park, New Zealand. Small reproduction only.

Richard Robinson / New Zealand Crayfish or Southern Rock Lobster (Jasus edwardsii) in Dusky Sound, Fiordland National Park, New Zealand.

Richard Robinson / New Zealand crayfish or southern rock lobster (Jasus edwardsii) in Dusky Sound, Fiordland National Park, New Zealand.

Richard Robinson / New Zealand Crayfish or Southern Rock Lobster (Jasus edwardsii) in Dusky Sound, Fiordland National Park, New Zealand. April 2014.(Cropped)

Richard Robinson / New Zealand Crayfish or Southern Rock Lobster (Jasus edwardsii) hides under a Fiordland Black Coral tree (Antipathella fiordensis) in Dusky Sound, Fiordland National Park, New Zealand. April 2014.

Richard Robinson / New Zealand Crayfish or Southern Rock Lobster (Jasus edwardsii) hides under a Fiordland Black Coral tree (Antipathella fiordensis) in Dusky Sound, Fiordland National Park, New Zealand. April 2014.

Richard Robinson / New Zealand Crayfish or Southern Rock Lobster (Jasus edwardsii) in Dusky Sound, Fiordland National Park, New Zealand.

Pete Oxford / Painted spiny lobsters (Panulirus versicolor) for sale, Suva Seafood Market, Viti Levu, Fiji, South Pacific, April 2014.

Wild Wonders of Europe / Lundgren / Danube crayfish (Astacus leptodactylus) hiding in the weed, Danube Delta, Romania, June.

Wild Wonders of Europe / Lundgren / Danube crayfish (Astacus leptodactylus) hiding in the weed, Danube Delta, Romania, June.

D. Parer & E. Parer-Cook / Platypus (Ornithorhynchus anatinus) male catching Common Yabby (Cherax destructor), native to Australia

MYN / Dirk Funhoff / Signal crayfish (Pacifastacus leniusculus) waving claw, Idar-Oberstein, Hunsruck, Germany, January. Meetyourneighbours.net project

MYN / Dirk Funhoff / Signal crayfish (Pacifastacus leniusculus) Idar-Oberstein, Hunsruck, Germany, January. Meetyourneighbours.net project

MYN / Dirk Funhoff / Signal crayfish (Pacifastacus leniusculus) claw, Idar-Oberstein, Hunsruck, Germany, January. Meetyourneighbours.net project

MYN / Dirk Funhoff / Signal crayfish (Pacifastacus leniusculus) Idar-Oberstein, Hunsruck, Germany, January. Meetyourneighbours.net project

MYN / Dirk Funhoff / Signal crayfish (Pacifastacus leniusculus) Idar-Oberstein, Hunsruck, Germany, January. Meetyourneighbours.net project

MYN / Dirk Funhoff / Calico crayfish (Orconectes immunis) Idar-Oberstein, Hunsruck, Germany, January. Meetyourneighbours.net project

MYN / Dirk Funhoff / Calico crayfish (Orconectes immunis) Idar-Oberstein, Hunsruck, Germany, January. Meetyourneighbours.net project

MYN / Dirk Funhoff / European crayfish (Astacus astacus) Idar- Oberstein, Hunsruck, Germany, January. Meetyourneighbours.net project

MYN / Dirk Funhoff / European crayfish (Astacus astacus) Idar- Oberstein, Hunsruck, Germany, January. Meetyourneighbours.net project

MYN / Dirk Funhoff / European Crayfish (Astacus astacus) Rhineland-Palatinate, Germany, January. Meetyourneighbours.net project

Sue Daly / Red Crayfish (Jasus edwardsii) Poor Knights Islands, New Zealand, January

Linda Pitkin / 2020VISION / White clawed crayfish (Austropotamobius pallipes) on river bed, viewed underwater, River Leith, Cumbria, England, UK, September 2012.

Linda Pitkin / 2020VISION / White clawed crayfish (Austropotamobius pallipes) on river bed, viewed underwater, River Leith, Cumbria, England, UK, September 2012.

Linda Pitkin / 2020VISION / White clawed crayfish (Austropotamobius pallipes) underwater on riverbed, showing defensive posture, River Leith, Cumbria, England, UK, September 2012.

Linda Pitkin / 2020VISION / White clawed crayfish (Austropotamobius pallipes) underwater on riverbed, displaying defensize posture, with hand reaching in, part of the Eden Rivers Trust crayfish capture and release population su...

Linda Pitkin / 2020VISION / White clawed crayfish (Austropotamobius pallipes) underwater on riverbed, showing defensive posture, River Leith, Cumbria, England, UK, September 2012.

Linda Pitkin / 2020VISION / White clawed crayfish (Austropotamobius pallipes) underwater on riverbed, River Leith, Cumbria, England, UK, September 2012.

Linda Pitkin / 2020VISION / White clawed crayfish (Austropotamobius pallipes) underwater on riverbed, River Leith, Cumbria, England, UK, September 2012.

Linda Pitkin / 2020VISION / White clawed crayfish (Austropotamobius pallipes) underwater on riverbed, River Leith, Cumbria, England, UK, September 2012.

Linda Pitkin / 2020VISION / White clawed crayfish (Austropotamobius pallipes) underwater on riverbed, River Leith, Cumbria, England, UK, September 2012.

Linda Pitkin / 2020VISION / White clawed crayfish (Austropotamobius pallipes) underwater on riverbed, River Leith, Cumbria, England, UK, September 2012.

Linda Pitkin / 2020VISION / White clawed crayfish (Austropotamobius pallipes) underwater on riverbed, River Leith, Cumbria, England, UK, September 2012.

Linda Pitkin / 2020VISION / White clawed crayfish (Austropotamobius pallipes) underwater on riverbed, River Leith, Cumbria, England, UK, September 2012.

Linda Pitkin / 2020VISION / Signal Crayfish (Pacifastacus leniusculus) on lake bottom, Wraysbury Lake, Middlesex, England, May

Linda Pitkin / 2020VISION / Signal Crayfish (Pacifastacus leniusculus) on lake bottom, Wraysbury Lake, Middlesex, England, May

Barry Mansell / Rusty grave digger / Burrowing crayfish (Cambarus miltus) Santa Rosa Co. Florida, USA, March Controlled conditions

Barry Mansell / Hatchet crayfish (Procambarus kilbyi) speckled phase, Bay Co, Florida, USA. Controlled conditions

Barry Mansell / Hatchet crayfish (Procambarus kilbyi) striped phase, Bay Co, Florida, USA. Controlled conditions

Barry Mansell / Fontal dwarf crayfish (Cambarellus schmitti) striped phase, Washington Co, Florida, USA. Controlled conditions

Barry Mansell / Ambiguous crayfish (Cambarus striatus) burrowing form (it can burrow into almost any substrate) West Florida, USA Controlled conditions

Barry Mansell / Rusty grave digger crayfish (Cambarus miltus) West Florida, USA Controlled conditions

Roland Seitre / Platypus (Ornithorhynchus anatinus) bill with a crayfish. Crayfish. Australian Reptile Park, Gosford, New South Wales.

Barry Mansell / Dougherty Plain cave crayfish (Cambarus cryptodytes) West Florida, USA, rare in Florida and imperiled in the only site in Georgia

Barry Mansell / Coastal lowland Cave crayfish (Procambarus leitheuseri) Crystal Springs Beach, Florida, USA

Barry Mansell / Withlacoochee light fleeing cave crayfish (Procambarus lucifugus lucifugus) Sweet Gum Cave, Florida, USA, October

Barry Mansell / Withlacoochee light fleeing cave crayfish (Procambarus lucifugus lucifugus) Sweet Gum Cave, Florida, USA, October

Barry Mansell / Coastal lowland Cave crayfish (Procambarus leitheuseri) Crystal Springs Beach, Florida, USA

Barry Mansell / Coastal lowland Cave crayfish (Procambarus leitheuseri) Crystal Springs Beach, Florida, USA

Barry Mansell / Coastal lowland Cave crayfish (Procambarus leitheuseri) Crystal Springs Beach, Florida, USA, August

Barry Mansell / Cave crayfish (Procambarus pallidus) Madison Co., Florida, USA, found in the Florida aquifer, has eye stalks but no functional eye or eye spot

Barry Mansell / Cave crayfish (Procambarus leitheuseri) Crystal Springs Beach, Florida, USA, August

Barry Mansell / Black Creek crayfish (Procambarus pictus) found in a few small streams in Clay, Putnam and Duval Counties, Florida, USA, Sprcies of Special Concern, March

Willem Kolvoort / European freshwater crayfish (Astacus astacus) crossing lake bed, Albania, Eastern Europe, May

Alex Mustard / 2020VISION / White-clawed crayfish (Austropotamobius pallipes) the endangered native crayfish species of the UK, Stoney Cove, Leicestershire, UK, December

Nature Production / Red / Louisianna swamp crayfish (Procambarus / Scapulicambarus clarkii) feeding on waterweed, Japan, August

Nature Production / Red / Louisianna swamp crayfish (Procambarus / Scapulicambarus clarkii) two males fighting, Fukuoka, Japan, March

Nature Production / Red / Louisianna swamp crayfish (Procambarus / Scapulicambarus clarkii) mating pair, Fukuoka, Japan, March

Michel Roggo / Spinycheek crayfish (Orconectes limosus) Europe

Barry Mansell / Male Burrowing crayfish (Procambarus rogersi campestris) Wakulla County, Florida, USA

Barry Mansell / Male Burrowing crayfish (Procambarus rogersi rogersi) Wakula County, West Florida, USA

Barry Mansell / Cave crayfish (Procambarus horsti) endemic to the Leon county area of Florida, found only in sinks or springs leading to underground aquifer, West Florida, USA

Barry Mansell / Male Fireback crayfish (Cambarus pyronotus) very narrowly restricted to a series of small ravine tributaries along the eastern bank of the upper Apalachicola River, Northern Liberty County, Florida, U...

Barry Mansell / Male Fireback crayfish (Cambarus pyronotus) very narrowly restricted to a series of small ravine tributaries along the eastern bank of the upper Apalachicola River, Northern Liberty County, Florida, U...

Barry Mansell / Male Fireback crayfish (Cambarus pyronotus) very narrowly restricted to a series of small ravine tributaries along the eastern bank of the upper Apalachicola River, Northern Liberty County, Florida, U...

Barry Mansell / Red-eyed Cave Crayfish (Procambarus erythrops) from an underground aquifer, Sims Sink, Swannee County, Florida, species of special concern, USA, Blind but with non-functional eye-spots that control...