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.
Dwarf Livebearer
One of the smallest fish species in the world, this tiny freshwater livebearer from the southeastern United States is prized for its miniature size and easy breeding.
freshwater
Dragon Goby
The Dragon Goby is a long, eel-like fish with a violet sheen and a large upturned mouth, found burrowing in muddy estuaries along the Americas' Atlantic coast.
brackish
Dwarf Lionfish
A compact, mottled lionfish with broad fan-like fins and venomous spines, ambushing prey on Indo-Pacific reefs.
reef
Cubbyu
A small, deep-bodied drum with a tall dorsal fin and faint dark stripes, often seen hovering near reef ledges in the western Atlantic.
reef
Electric Ray
A round-bodied ray capable of generating a powerful electric shock from specialized organs, used to stun prey and deter predators.
cartilaginous
Corydoras
A small, armored bottom-dwelling catfish native to South American streams, Corydoras species are recognized by their rows of bony plates, paired barbels, and constant substrate-sifting behavior in search of food.
freshwater
Discus
A round, flattened Amazonian cichlid prized for its vivid patterns and colors, considered one of the most striking freshwater aquarium fish and a demanding species to keep well.
freshwater
European Flounder
The European flounder is a right-eyed flatfish notable for its unusual tolerance of low salinity, regularly venturing far up rivers and estuaries.
brackish
Emerald Rainbowfish
A deep-bodied rainbowfish endemic to Lake Wanam in Papua New Guinea, with mature males displaying a brilliant iridescent emerald-green sheen.
freshwater
European Grayling
The European grayling is a slender salmonid famous for its tall, sail-like, iridescent dorsal fin, found in cold, clear rivers and lakes across much of Europe.
freshwater
Cutthroat Trout
A native western North American trout named for the distinctive red-orange slash marks under its jaw, found in an array of subspecies across cold streams and mountain lakes.
freshwater
European Conger
A large, powerfully built grey eel that shelters in rocky crevices and shipwrecks across the Northeast Atlantic and Mediterranean, among the largest eel species in the region.
saltwater
Doubletooth Surgeonfish
A sawtail surgeonfish of the genus Prionurus, marked by rows of forward-angled bony 'teeth' on the tail base instead of a single blade-like spine; found on rocky reefs of the eastern tropical Atlantic.
reef
Electric Catfish
An African freshwater catfish capable of generating strong electric discharges from specialized body tissue used for hunting and defense.
freshwater
Emperor Cichlid
The largest cichlid species in the world, the emperor cichlid grows to nearly a meter long in the deep waters of Lake Tanganyika and is notable for spawning only once before dying shortly after.
freshwater
Dolly Varden
A char of Pacific coastal rivers named for a colorfully dressed Dickens character, closely related to and often confused with Arctic Char.
freshwater
Dog Salmon Herring
Despite the name, this is the chum salmon, nicknamed 'dog salmon' for its prominent canine-like spawning teeth — a true Pacific salmon, not a herring.
saltwater
Dwarf Seahorse
One of the smallest seahorse species in the world, standing barely a few centimeters tall and clinging to seagrass blades in shallow waters of the southeastern United States and Bahamas.
saltwater
Denison Barb
A striking torpedo-shaped barb endemic to fast hill streams of India's Western Ghats, known for its bold red-black-yellow stripe and endangered status.
freshwater
Dogtooth Tuna
A powerful reef-associated tuna of the Indo-Pacific, named for its large, dog-like teeth, often encountered patrolling steep drop-offs and current-swept reef edges.
reef
Dragon Moray
One of the most ornately marked moray eels, easily recognized by its long tubular nostrils resembling horns and a striking mottled orange, white, and black pattern that has made it a favorite subject for underwater photographers.
reef
Diamond Goby
A slender, sand-sifting goby with rows of orange spots, prized for cleaning aquarium sand beds. Found on shallow lagoon flats throughout the Indo-Pacific.
reef
Electric Yellow Cichlid
A vividly yellow mbuna cichlid endemic to Lake Malawi's rocky shorelines, popular in aquariums for its bright, almost uniform coloration and relatively peaceful temperament.
freshwater
Cuckoo Wrasse
A vividly patterned wrasse of the Northeast Atlantic and Mediterranean, with males displaying bold blue and orange stripes and females a softer pink patterned with black-edged white spots.
reef
Cusk
The cusk is a solitary, eel-like member of the cod family found on deep rocky bottoms of the North Atlantic, recognized by its single long dorsal fin and thick lips.
saltwater
Electric Blue Hap
One of the most vividly colored Lake Malawi haplochromine cichlids, males display an intense electric-blue body that makes this predatory species a standout among the lake's rock-dwelling cichlids.
freshwater
Cottonmouth Jack
A plain, silvery-grey deep-water jack named for the pale interior of its mouth, found over continental shelves and slopes across tropical oceans worldwide.
pelagic
Dragon Wrasse
A reef wrasse whose juveniles mimic drifting algae with wild fin extensions, while adults become stout, green-bodied rock-flippers that hunt buried invertebrates.
reef
Eagle Ray
A diamond-shaped ray with a distinctive protruding duck-like snout, often seen gliding gracefully near the seafloor in coastal waters of the eastern Atlantic and Mediterranean.
cartilaginous
Diamond Tetra
A deep-bodied Venezuelan characin famed for its sparkling iridescent scales, endemic to the ecologically stressed Lake Valencia basin.
freshwater
Delhezi Bichir
A boldly barred Congo Basin fish with a series of dark vertical bands along its yellow-tan body and a row of spiny finlets along its back.
freshwaterDragonfish
Dragonfish are elongated, predatory deep-sea fish with needle-sharp teeth and a long luminous chin barbel used to lure prey in the permanently dark mesopelagic zone.
deepsea
Chinese High-Fin Banded Shark
Despite its name, the Chinese High-Fin Banded Shark is not a shark at all but a large freshwater sucker native to China's Yangtze River basin, known for its tall sail-like dorsal fin.
freshwater
Deep-sea Smelt
A small, silvery-bodied deep-sea fish that drifts through the dark midwater zone feeding on tiny plankton, forming a key link in deep ocean food webs.
deepsea
Cleaner Wrasse
The Cleaner Wrasse is a slender fish with a bold black horizontal stripe and blue body, famous for removing parasites and dead tissue from other reef fish at dedicated cleaning stations.
reef
Dover Sole
The Dover sole is a slippery-skinned, right-eyed flatfish of the North Pacific, unusual among soles for living on deep continental slope bottoms far offshore.
deepsea
Common Skate
One of the largest skates in the world, now Critically Endangered after severe historical overfishing across its North Atlantic range.
cartilaginous
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
Chestnut Lamprey
The chestnut lamprey is a freshwater parasitic lamprey of central North America named for its reddish-brown coloration, native to Mississippi and Great Lakes basin rivers and lakes.
freshwater
Deep-sea Hatchetfish
A small, silvery, laterally flattened deep-sea fish shaped like a hatchet blade, using rows of downward-pointing light organs to mask its silhouette from predators lurking below.
deepsea
Common Pleco
A large, heavily armored South American catfish with a suckermouth used to graze algae and biofilm from rocks and submerged wood.
freshwater
Dwarf Pufferfish
The Dwarf Pufferfish is one of the world's smallest puffers, a freshwater species from southern India prized for its tiny size and expressive, alert behavior.
freshwater
Coelacanth
The coelacanth is an ancient, deep-dwelling lobe-finned fish once known only from fossils, famously rediscovered alive off South Africa in 1938.
deepsea
Dusky Shark
A large, robust requiem shark found along continental coastlines worldwide, notable for its slow growth and long-distance migrations.
saltwater
Common Sole
The common sole is a slender, right-eyed flatfish of European coastal waters, recognizable by its elongated oval body and small, curved mouth adapted for nighttime foraging.
saltwater
Diamond Killifish
A tiny, unusually deep-bodied killifish from Gulf Coast salt marshes, named for its compressed, diamond-shaped profile. It tolerates wide swings in salinity within tidal creeks and marsh pools.
brackish
China Rockfish
Easily recognized by a bold yellow stripe running down its black body, the China rockfish is a small, secretive reef dweller of the northeastern Pacific.
saltwater
Cunner
A small, cold-hardy wrasse with highly variable coloring, found on rocky reefs and kelp beds along the western Atlantic and known for becoming dormant in winter.
saltwater