Fish Encyclopedia
Search and identify 1,000+ fish species — freshwater, saltwater, reef, and pelagic — with habitat, size, diet, behavior, and how to tell them apart.
Beluga Sturgeon
One of the largest anadromous fish in the world, native to the Caspian and Black Sea basins. It migrates into major rivers like the Volga and Danube to spawn and is critically endangered.
brackish
Sculpin
A broad-headed, bottom-dwelling fish of the family Cottidae, represented here by the widespread Pacific Staghorn Sculpin, known for its large fan-like pectoral fins and mottled camouflage on sandy and muddy bottoms.
saltwater
Sturgeon
An ancient family of large, armored bony fish with bony scutes instead of scales and a shark-like barbeled snout. Sturgeon migrate between rivers and the sea to spawn and are among the most endangered fish groups.
brackish
Swordtail
Named for the elongated, sword-like extension on the male's tail fin, this energetic livebearer from Mexico and Central America is a long-standing favorite in freshwater aquariums.
freshwater
Striped Marlin
A swift, streamlined billfish famous for its tall, sail-like blue dorsal fin and rows of pale vertical stripes, ranging widely through the Pacific and Indian Oceans as a top offshore predator.
pelagic
Sailfin Molly
Named for the male's spectacular, sail-like dorsal fin, this coastal livebearer from the southeastern United States and Mexico is a striking sight in brackish marshes and aquariums alike.
brackish
Ruby Seadragon
The ruby seadragon is a rare, deep-dwelling relative of the leafy and weedy seadragons discovered in 2015 off Western Australia. Unlike its relatives, it lacks leaf-like appendages and has a distinctive reddish body.
reef
Bagre Catfish
A silvery marine and estuarine catfish of the western Atlantic and Gulf of Mexico, recognizable by its elongated sail-like dorsal fin filament and mouth-brooding parenting behavior.
saltwater
White's Seahorse
White's seahorse is an endangered species endemic to the temperate estuaries of eastern Australia, best known for colonizing artificial structures like marina pylons and 'seahorse hotels' installed for conservation.
reef
Lionfish
A striking, striped reef predator native to the Indo-Pacific, now a widespread and ecologically disruptive invasive species across the Western Atlantic and Caribbean, easily recognized by its fan-like fins and venomous spines.
reef
Atlantic Hagfish
The Atlantic hagfish is a primitive, eel-like, jawless scavenger known for producing enormous quantities of defensive slime and for its ability to feed inside the carcasses of dead or dying animals on the seafloor.
deepsea
American Gizzard Shad
A deep-bodied, blunt-snouted herring relative common in lakes and rivers across eastern and central North America, the American Gizzard Shad is a highly abundant forage fish named for its muscular, gizzard-like stomach.
freshwater
Mudskipper
An amphibious goby that spends much of its life out of water, hopping across mudflats on muscular pectoral fins. Bulging, periscope-like eyes let it watch for predators while it hunts and defends its burrow.
brackish
Eastern Mosquitofish
Native to the Atlantic coastal plain of the eastern United States, the eastern mosquitofish is nearly identical to its western relative and has likewise been widely introduced worldwide for mosquito control.
freshwater
Snakeskin Gourami
A large, elongated Southeast Asian gourami named for the diagonal, snakeskin-like striping pattern across its olive-brown flanks, widely distributed through floodplain and canal habitats.
freshwater
Harlequin Tuskfish
A vividly colored wrasse with a turquoise-blue body crossed by orange bars and prominent protruding tusk-like teeth used to crush hard-shelled prey. It inhabits coral-rich reef slopes across the western Pacific.
reef
Gizzard Shad
A deep-bodied, silvery freshwater fish easily recognized by its blunt, rounded snout and long, whip-like filament trailing from the last dorsal fin ray, common in rivers, lakes, and reservoirs across North America.
freshwater