''Cancer productus'', one of several species known as red rock crabs, is a crab of the genus ''

Cancer Cancer is a group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body. These contrast with benign tumors, which do not spread. Possible signs and symptoms include a lump, abnormal bl ...

'' found on the western coast of North America. This species is commonly nicknamed the Pearl of the

Pacific Northwest The Pacific Northwest (sometimes Cascadia, or simply abbreviated as PNW) is a geographic region in western North America bounded by its coastal waters of the Pacific Ocean to the west and, loosely, by the Rocky Mountains to the east. Though ...

Description

''Cancer productus'' has

carapace A carapace is a dorsal (upper) section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tortoises, the und ...

teeth that are somewhat broad and rounded with teeth between the eyes of nearly equal size and shape. The carapace of ''C. productus'' is widest at the posterior-most tooth, up to 20.0 cm wide. The pincers are large with distinctive black tips. This species lacks serrations or projections on the ventral side of the claws. Adults have a brick-red coloration throughout. The coloration of juveniles is diverse, often white, sometimes with red spots, or zebra-striped.

Similar species

Dungeness crab The Dungeness crab (''Metacarcinus magister'') is a species of crab inhabiting eelgrass beds and water bottoms along the west coast of North America. It typically grows to across the carapace and is a popular seafood. Its common name comes fr ...

(''Metacarcinus magister'') has serrations on the dorsal side of the

cheliped A chela ()also called a claw, nipper, or pinceris a pincer-like organ at the end of certain limbs of some arthropods. The name comes from Ancient Greek , through New Latin New Latin (also called Neo-Latin or Modern Latin) is the revival ...

s and lacks black tips. The graceful rock crab ('' Metacarcinus gracilis'') has a single projection on the dorsal side of the chelipeds and also lacks black tips, and the widest point of carapace is at the second posterior-most tooth. The pygmy rock crab ('' Glebocarcinus oregonensis'') has black-tipped chelipeds, but has large

tubercle In anatomy, a tubercle (literally 'small tuber', Latin for 'lump') is any round nodule, small eminence, or warty outgrowth found on external or internal organs of a plant or an animal. In plants A tubercle is generally a wart-like projection ...

s on the dorsum. ''Glebocarcinus oregonensis'' is also much smaller, such that a ''C. productus'' of similar size would generally have a striking juvenile coloration.

Cancer pagurus ''Cancer pagurus'', commonly known as the edible crab or brown crab, is a species of crab found in the North Sea, North Atlantic Ocean, and perhaps the Mediterranean Sea. It is a robust crab of a reddish-brown colour, having an oval carapace with ...

is very similar, but distinguished by its non-overlapping range.

Range and habitat

''Cancer productus'' ranges from

Kodiak Island Kodiak Island (Alutiiq language, Alutiiq: ''Qikertaq''), is a large island on the south coast of the U.S. state of Alaska, separated from the Alaska mainland by the Shelikof Strait. The largest island in the Kodiak Archipelago, Kodiak Island is ...

Alaska Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U.S ...

, to Isla San Martine,

Baja California Baja California (; 'Lower California'), officially the Free and Sovereign State of Baja California ( es, Estado Libre y Soberano de Baja California), is a state in Mexico. It is the northernmost and westernmost of the 32 federal entities of Mex ...

. It inhabits mid-

intertidal The intertidal zone, also known as the foreshore, is the area above water level at low tide and underwater at high tide (in other words, the area within the tidal range). This area can include several types of habitats with various species ...

waters to 79 m depth.

Biology

''Cancer productus'' is

carnivorous A carnivore , or meat-eater (Latin, ''caro'', genitive ''carnis'', meaning meat or "flesh" and ''vorare'' meaning "to devour"), is an animal or plant whose food and energy requirements derive from animal tissues (mainly muscle, fat and other ...

; in

Puget Sound Puget Sound ( ) is a sound of the Pacific Northwest, an inlet of the Pacific Ocean, and part of the Salish Sea. It is located along the northwestern coast of the U.S. state of Washington. It is a complex estuarine system of interconnected m ...

it will crush

barnacle A barnacle is a type of arthropod constituting the subclass Cirripedia in the subphylum Crustacea, and is hence related to crabs and lobsters. Barnacles are exclusively marine, and tend to live in shallow and tidal waters, typically in erosive ...

s with its large pincers for consumption. Small living crabs and dead

fish Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% ...

are also eaten. Mating in this species occurs when the female is soft-shelled from October to June in Puget Sound. The male can often been seen guarding females until molting during this time. This species is known to be a favorite prey item of the giant Pacific octopus, '' Enteroctopus dofleini''.

Fishery

''Cancer productus'' is harvested by sport and commercial fishermen in California, mostly from Morro Bay south. The California rock crab fishery is made up of three species – the yellow rock crab ('' C. anthonyi''), the brown rock crab ('' R. antennarium''), and the red rock crab (''C. productus''). Rock crab landings for 1999 were 790,000 pounds and have averaged 1.2 million pounds per year from 1991–1999. It is not as sought after as

due to the considerably lower amount of flesh. However, the flesh has a delicate flavor and slightly sweet taste. The similar ''

'' has a major commercial fishery in western Europe. Both males and females with a carapace exceeding may be harvested in Washington, when in season.

References

External links

*
Walla Walla University Marine Inverts Key: ''Cancer productus''
{{Taxonbar, from=Q5031457 Cancroidea Crustaceans of the eastern Pacific Ocean Crustaceans described in 1839 Fauna of the San Francisco Bay Area