Fish

Cod tongue

Cod tongue is a dish of flesh from a cod's throat and lower jaw, a traditional Newfoundland food, flour-coated and fried, and also eaten in Norway and Portugal.

Coelacanth (Latimeria): lobe-finned "living fossil" fish thought extinct ~65-70 million years until the 1938 Chalumna River catch; two species, L. chalumnae and L. menadoensis; lungfish, not coelacanth, is the tetrapods' closest living relative.

Coho salmon

Coho salmon (Oncorhynchus kisutch), the silver salmon, is an anadromous Pacific salmon from Alaska to central California, also introduced in the Great Lakes; one ESU is ESA-endangered, three threatened.

Cololabis saira

Cololabis saira, the Pacific saury (Japanese sanma, サンマ), is a small pelagic fish of the North Pacific from Japan to the Gulf of Alaska, fished mainly by stick-held dip net and managed by the NPFC; the stock is overfished, with a 2025 catch limit of 202,500 metric tons.

Colossoma macropomum

Colossoma macropomum, tambaqui or black pacu, a large Serrasalmidae fish of the Amazon and Orinoco basins; second largest scaled Amazon fish, seed-eating, heavily farmed, IUCN Near Threatened and Vulnerable in Brazil.

Combtooth blenny

Combtooth blennies (Blenniidae) are about 400 species of small scaleless marine fishes with a single comblike row of incisiform teeth, living in shallow tropical and subtropical habitats; molecular phylogeny recognizes 13 unranked clades and four intertidal invasions.

Common dace

Common dace (Leuciscus leuciscus, Eurasian dace) is a small Leuciscidae river fish across Europe and the Volga-Ural basins; IUCN Least Concern, invasive in Ireland, spawning on gravel beds February to May.

Common goldfish

Developed in China, the Common goldfish (Carassius auratus) is a domesticated Cyprinidae carp. It is plain-bodied, tolerates poor water, and can live up to 43 years.

Common snook

Common snook (Centropomus undecimalis), also called linesider or robalo, is a Centropomidae game fish ranging from the US mid-Atlantic to Brazil, abundant in Florida estuaries, managed as a recreational-only gamefish with a 40% SPR goal.

Conger conger

Conger conger, the European conger (conger eel), is the largest eel in Europe, a benthic Anguilliformes predator from Norway to Senegal and the Mediterranean, reaching 300 cm and 110 kg, semelparous, IUCN Least Concern.

Coniunctio

Coniunctio is an extinct Triassic elasmobranch (cartilaginous fish) genus established by Johns in 1997, known from ichthyoliths in British Columbia, with species C. aequirugosa (type) and C. multirugosa, defining a Ladinian biozone.

Cookiecutter shark

Cookiecutter shark (Isistius brasiliensis), cigar shark, a small mesopelagic squaliform shark of tropical and subtropical oceans that removes plugs of flesh from large prey, leaving crater wounds; feeds mainly on small micronekton, bioluminescent, has bitten swimmers and submarines.

Coptodon zillii

Coptodon zillii, redbelly tilapia, formerly Tilapia zillii, is a cichlid fish native to northern Africa and the Middle East, widely introduced on every continent, tolerant of 6.5–42.5 °C and salinity to 45 ppt, and ranked among the world's most invasive freshwater fishes.

Coregonus

Coregonus is a salmonid genus of about 80-89 whitefish and cisco species of northern lakes and seas, including C. artedi and C. clupeaformis; threatened by overfishing, invasives, and warming, with active restoration in the Great Lakes.

Coregonus albula

Coregonus albula, the vendace or Baltic cisco, is a small planktivorous salmonid fish of northern European lakes and the brackish Baltic Sea, spawning in late autumn, supporting major Finnish and Swedish roe fisheries, and forming a taxonomically debated complex with the least cisco.

Coregonus artedi

Coregonus artedi (cisco, lake herring, tullibee) is a North American coldwater salmonid of Canada and the northern US, once dominant in the Great Lakes, now widespread mainly in Lake Superior and the focus of restoration programs.

Coregonus clupeaformis

Coregonus clupeaformis, the lake whitefish (grand corégone), is a North American salmonid of large cold lakes and rivers, a major Canadian commercial fish with subterminal mouth, fall shoal spawning, and reproductively isolated lake species pairs.

Coregonus lavaretus

Coregonus lavaretus, the European whitefish (powan, schelly, gwyniad), is a salmonid fish of a taxonomically disputed species complex spanning Siberia to the Alps, with three mtDNA lineages, seven native British populations, and Vulnerable IUCN status.

Corvina

Corvina is a Spanish/Portuguese common name for various sciaenid (drum and croaker) fishes, including Cynoscion xanthulus, C. parvipinnis, and Argyrosomus regius; the genus Corvina itself is an invalid synonym of Sciaena.

Coryphaenoides rupestris

The roundnose grenadier, Coryphaenoides rupestris, is a rattail fish of the North Atlantic's continental slopes, target of a deep-water trawl fishery that peaked at almost 84,000 t in 1971.

Cottidae

Cottidae, the sculpins or bullheads, is a family of about 264 to 300 benthic northern fish genera and species, mostly marine but with many freshwater Cottus, revised in 2014 into six cottoid families.

Cow shark

Cow sharks (Hexanchidae), also called sixgill and sevengill sharks, are deepwater Hexanchiformes with 6 or 7 gill slits, one rear dorsal fin, an anal fin, and saw-like lower teeth; four species, 1.4 to 4.8 m, ovoviviparous.

Crappie

Crappie: two North American freshwater sunfish species, black crappie (Pomoxis nigromaculatus) and white crappie (Pomoxis annularis), popular panfish distinguished by dorsal spine count (7-8 vs 5-6), stocked widely across the US.

Cyclopterus lumpus

Cyclopterus lumpus, the lumpfish or lumpsucker, a North Atlantic ball-shaped fish fished for caviar-substitute roe and used as cleaner fish against sea lice; IUCN Near Threatened, Threatened in Canada, Danish fishery closed 2025.

Cymothoa exigua

Cymothoa exigua, the tongue-eating louse (tongue biter), is a cymothoid isopod that enters fish through the gills, destroys the tongue, and replaces it, the only known parasite to functionally replace a host organ.

Cynoscion nebulosus

Cynoscion nebulosus, the spotted seatrout or speckled trout, a sciaenid drum fish of western Atlantic estuaries from Cape Cod to the Gulf of Mexico, with black spots, canine teeth, night spawning, and a major recreational fishery.

Cynoscion regalis

Cynoscion regalis, the weakfish, is a marine drum fish of the Atlantic coast of North America, common from New York to North Carolina and named for its fragile mouth.

Cyprinidae

Cyprinidae, the carp and minnow family of order Cypriniformes, is the largest freshwater fish family with over 1,840 species; toothless jaws, pharyngeal teeth, kinethmoid; recently split into several families.

Cypriniformes

Cypriniformes: the most diverse order of freshwater fishes (carps, minnows, loaches, suckers), about 3,000-4,200 species, toothless jaws with pharyngeal teeth on the fifth ceratobranchial, a Weberian apparatus, and two suborders, Cobitoidei and Cyprinoidei.