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.
Siamese Algae Eater
A slim, torpedo-shaped Southeast Asian minnow relative well known among aquarium keepers for actively grazing on a wide range of algae types.
freshwater
Pouting
Also called bib, the Pouting is a deep-bodied, coppery-bronze gadoid common around rocky reefs and wrecks of the northeastern Atlantic and Mediterranean.
saltwaterSevruga
The sevruga, or starry sturgeon, is a slender anadromous sturgeon of the Caspian, Black, and Azov Sea basins, known for its long upturned snout and rows of star-shaped bony scutes.
brackish
Queen Parrotfish
A blue-green Caribbean parrotfish with a bold yellow band across the snout, commonly seen grazing algae along reef slopes and flats throughout the region.
reef
Shortfin Molly
A hardy, adaptable livebearer native to Mexico and Central America, prized in the aquarium trade for its tolerance of varied water chemistry.
freshwater
Purple Spotted Gudgeon
A stocky, olive-brown Australian freshwater fish covered in scattered iridescent purple-blue spots, favoring weedy, slow-moving streams and lagoons.
freshwater
Shortbill Spearfish
A slender billfish with an unusually short bill relative to its body, found in warm offshore waters worldwide and considered the smallest of the true spearfish.
pelagic
Rachovi Killifish
A vividly colored annual killifish from coastal Mozambique, with males showing a turquoise body and a tricolor red-yellow-blue tail. It lives in temporary floodplain pools near Beira.
freshwater
Sheepshead Bream
The sheepshead bream, or white seabream, is a silvery sparid marked by dark vertical bars and a black tail-base spot, common over rocky reefs and seagrass in the Mediterranean and eastern Atlantic.
reef
Pink Skunk Clownfish
A pale pink anemonefish with a single white stripe running down its back, found living among sea anemones on reefs across the Indo-Pacific.
reef
Rock Bass
A robust, bronze-colored sunfish relative with striking red eyes, often found around rocky cover in clear streams and lakes of eastern and central North America.
freshwater
Lyretail Killifish
A slender, non-annual West African killifish named for the male's elegant lyre-shaped tail, ranging in color from golden-orange to deep red across its native populations.
freshwater
Robust Ghost Pipefish
The robust ghost pipefish is the largest species in its family, with a plainer, leaf-like body that mimics drifting seagrass, algae, or sargassum rather than the frillier crinoid-mimicking patterns of its relatives.
reef
Pacific Herring
A slender, silvery schooling fish closely related to the Atlantic Herring, found in cold coastal waters across the North Pacific, where it forms a critical forage base for fish, seabirds, and marine mammals.
pelagic
Redtail Catfish
A large South American river catfish easily recognized by its dark body, cream underside, and vivid orange-red tail fin.
freshwater
Pearl Danio
A slender, iridescent danio with a shifting pearly sheen of blue, pink, and gold along its flanks, native to fast-flowing Southeast Asian streams.
freshwater
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
Pacific Cod
A heavy-bodied, bottom-dwelling relative of the Atlantic Cod found across the cold North Pacific, recognized by its large head, chin barbel, and mottled brown coloring.
saltwater
Reef Needlefish
A long, slender, silvery needlefish with elongated toothy jaws, commonly seen cruising just below the surface over Indo-Pacific coral reefs and reef flats.
reefPacific Menhaden
A deep-bodied, silvery schooling fish found along the Pacific coast of South America, marked by a row of dark spots along its flank and adapted to feeding within the highly productive Humboldt Current upwelling system.
pelagic
Rummy-nose Tetra
A small schooling Amazonian tetra known for its bright red-orange snout and a bold black-and-white striped tail fin, prized in aquariums for its striking coloration and tight shoaling behavior.
freshwater
Pacific Mackerel
A schooling pelagic fish of the eastern Pacific with an iridescent blue-green back marked by irregular dark bars and scattered spots along its lower flanks.
pelagic
Round Herring
Named for its unusually rounded, cylindrical body, the Round Herring is a schooling coastal pelagic fish found in temperate and subtropical seas worldwide, serving as an important forage species for larger predators.
pelagic
Pacific Lamprey
The Pacific lamprey is a jawless, anadromous fish with a toothed sucking disc mouth, found along Pacific coastlines from Baja California to Japan and Alaska.
saltwaterRibbon Halfbeak
An extraordinarily thin, ribbon-shaped halfbeak of the open ocean, with a long needle-like lower jaw and greatly elongated fins that let it skitter and glide across the surface.
pelagicPacific Bluefin Tuna
A massive, warm-bodied tuna capable of ocean-basin migrations across the entire North Pacific, recognized by its deep, torpedo-shaped body and short pectoral fins.
pelagic
Rock Cook
A tiny olive-brown wrasse of northeastern Atlantic kelp reefs, the Rock Cook forages among rocks and crevices and can change sex during its lifetime.
saltwater
Pilotfish
A boldly barred open-ocean jack famous for closely trailing sharks and other large marine animals for shelter and feeding opportunities.
pelagic
Rock Goby
A small, mottled goby common in rocky tide pools along European and North African coasts, easily spotted darting between rocks at low tide.
saltwater
Parkinson's Rainbowfish
A large, robust rainbowfish from the eastern rivers of Papua New Guinea, with mature males displaying a striking golden-orange rear half contrasting with a bluish-silver front.
freshwater
Rosy Barb
A hardy, active barb whose silvery body flushes rosy pink to red during breeding condition, especially pronounced in males.
freshwater
Pearlscale Butterflyfish
A western-Pacific butterflyfish with a cross-hatched pearly body and a bright orange rear and tail.
reef
Rex Sole
A slender, deep-dwelling northeastern Pacific flatfish notable for unusually long pectoral fins and plain light brown coloration on cold continental shelf and slope bottoms.
deepsea
Peacock Blenny
A shallow-water Mediterranean blenny in which breeding males grow a tall fleshy head crest and a bold eyespot on the dorsal fin.
saltwater
Ribbon Eel
The Ribbon Eel is a slender, brightly colored moray that changes from a black juvenile to a blue male to a yellow female over its lifetime while anchored in a sand burrow.
reef
Passer Angelfish
An eastern-Pacific angelfish with a dark blue body, a single white vertical bar, and a yellow tail.
reef
Rosy Loach
The Rosy Loach is a tiny, delicately colored nano loach from Myanmar's slow-moving, vegetated streams and pools, prized for its diminutive size and rosy-pink hues.
freshwater
Pacific Saury
A slender, silvery, beaked schooling fish of the temperate North Pacific, closely related to needlefish, marked by a row of small finlets near its tail.
pelagic
Redbanded Seabream
The redbanded seabream is a deep-bodied, pinkish-red sparid marked by four to five dark vertical bands, found over rocky and sandy bottoms in the eastern Atlantic and Mediterranean.
saltwater
Opaline Gourami
A marbled blue-and-silver color variety of the Three Spot Gourami, bred for its swirling opalescent pattern while retaining the same hardy biology and behavior as the wild form.
freshwater
Round Stingray
A small, round-bodied stingray common in shallow sandy surf zones along the Pacific coast, notable for large seasonal aggregations in warm bays.
cartilaginous
Marbled Swamp Eel
A snake-like, limbless eel of Central and South American swamps and slow rivers, marked with a mottled, marbled pattern and equipped with air-breathing lungs-like tissue for surviving in stagnant water.
freshwater
Rosy Rockfish
A small, brightly colored rockfish with rose-pink coloring and dark saddle blotches, found on rocky reefs along the California coast.
saltwater
Neon Goby
A tiny reef fish with an electric blue stripe running nose to tail, best known for cleaning parasites off larger reef fish.
reef
Regal Tang
An unmistakable royal-blue surgeonfish with a black palette pattern and bright yellow tail, popularized worldwide as the character Dory, commonly seen darting among branching corals.
reef
Mosquitofish
A small, drab livebearer native to the central and southeastern United States, the mosquitofish is famous for its voracious appetite for mosquito larvae and has been introduced worldwide for pest control.
freshwater
Rohu
A large South Asian river carp with a streamlined, silvery-grey body, widely farmed across the Indian subcontinent as a major aquaculture species and prized angling fish.
freshwater
Masu Salmon
Masu salmon is the southernmost and westernmost Pacific salmon species, native to Japan, Korea, and the Russian Far East, notable for males that can mature and spawn entirely within freshwater.
freshwater