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.
Bichir
The bichir is a primitive, air-breathing freshwater fish of African rivers and swamps, genus Polypterus, known for its snake-like armored body and spiny dorsal finlets.
freshwater
Blackspotted Puffer
The Blackspotted Puffer, also called the dog-faced puffer, is a small reef pufferfish with a gray, yellow, or blue body scattered with a few large dark spots.
reef
Banded Butterflyfish
A white Caribbean butterflyfish crossed by bold black vertical bands, including one masking the eye.
reef
Bleak
A small, slender, silvery cyprinid, the bleak forms huge surface shoals in rivers and lakes, snapping at insects and once prized for its scales used in imitation pearls.
freshwater
Balloon Molly
A selectively bred molly variety with a distinctive rounded, ball-shaped body caused by a spinal curvature, developed and maintained through aquarium breeding.
freshwater
Black Skirt Tetra
A silvery-gray tetra with a flowing black skirt-like tail and fins, whose dark coloration typically fades somewhat as the fish matures.
freshwater
Big-belly Seahorse
The largest seahorse species in the world, recognized by its notably rounded, protruding belly and mottled brown-yellow coloration, found along the temperate coasts of Australia and New Zealand.
saltwater
Black Phantom Tetra
A gray-black Paraguay basin characin known for its dramatic sail-like dorsal fin displays and mild social hierarchy behavior among males.
freshwater
Bicolor Damselfish
A small reef fish sharply split into a dark front half and a pale rear half, common on Caribbean and western Atlantic coral reefs where it defends algae-covered territories.
reef
Blackspotted Topminnow
A slender killifish of Gulf Coastal Plain streams, marked by rows of dark spots along its sides rather than a solid stripe. It favors clear, vegetated streams from Texas to Alabama.
freshwater
Banggai Cardinalfish
The Banggai Cardinalfish is a striking silver-and-black fish with long trailing fins and bold white spots, native to a tiny area of Indonesia and listed as Endangered in the wild.
reef
Blackfin Clownfish
An orange anemonefish with a single white head bar and distinctive black-edged pelvic and anal fins, endemic to reefs around the Maldives and Sri Lanka.
reef
Barracuda
A large, torpedo-shaped predatory fish found around tropical reefs, seagrass beds, and open coastal waters worldwide, easily identified by its underbite jaw and fang-like teeth.
reef
Bigeye Tuna
A large, deep-diving tuna named for its notably large eyes, adapted for hunting in the dim light of deep water far below the ocean surface.
pelagic
Banded Rudderfish
A western Atlantic jack whose boldly banded juveniles shelter beneath floating debris, later maturing into plainer, olive-silvery adults resembling small amberjacks.
saltwater
Black Crappie
A silvery panfish mottled with irregular dark speckling, closely related to the White Crappie but preferring clearer water, and one of the most popular schooling panfish in North America.
freshwater
Banded Killifish
A slender, silvery killifish common in vegetated lakes and slow streams of eastern North America, marked with numerous thin dark vertical bars along its flanks.
freshwaterBlack Hagfish
The black hagfish is a jawless, deep-sea scavenger found on the muddy continental slope off the Pacific coast of North America, notable for its uniformly dark coloration.
deepsea
Bat Ray
A large, dark-backed eagle ray of the eastern Pacific coast, often seen gliding over sand flats or excavating pits to unearth buried prey.
cartilaginous
Black Marlin
A massive, powerful billfish of the Indo-Pacific known for its rigid, immovable pectoral fins and status as one of the largest bony fish in the ocean.
pelagic
Atlantic Pollock
A fast, schooling North Atlantic gadid with a dark streamlined body and pale lateral line, often found swimming in open water over the shelf.
pelagic
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
Bala Shark
A torpedo-shaped, silver freshwater fish named for its shark-like body outline, though it is a true minnow relative, not a shark. Bold black margins on its fins make it a striking, fast-swimming schooler of Southeast Asian rivers.
freshwater
Atlantic Bluefin Tuna
A massive, torpedo-shaped, deep blue-backed tuna built for speed and long-distance migration across the Atlantic Ocean and Mediterranean Sea.
pelagic
Atlantic Mudskipper
An amphibious goby that hops and skips across mangrove mudflats using muscular pectoral fins, breathing air through its skin and mouth lining when out of water.
brackish
Atlantic Menhaden
A deep-bodied, oily, silvery schooling fish found in vast numbers along the U.S. Atlantic coast, notable for a large dark shoulder spot and its outsized ecological role as a filter-feeding forage species.
pelagic
Ballyhoo
A slender, silvery halfbeak of coastal Atlantic waters, easily recognized by its long lower jaw tipped in red-orange, often seen skittering across the surface in schools.
saltwater
Atlantic Mackerel
A fast-swimming schooling fish with iridescent blue-green wavy stripes across its back, found in cold and temperate waters on both sides of the North Atlantic.
pelagic
Atlantic Blue Marlin
A massive, powerful billfish of the open Atlantic, known for its cobalt-blue back, silvery flanks, and a long spear-like bill used to stun prey.
pelagic
Banjo Catfish
A flattened, camouflaged South American catfish with a body shape resembling a banjo, spending most of its time buried in sand or hidden among leaf litter.
freshwater
Atlantic Saury
A slender, silvery, beaked fish of the open North Atlantic, closely related to needlefish, recognized by its elongated jaws and a row of small finlets near the tail.
pelagicAtlantic Herring
A slender, silvery schooling fish that forms some of the largest shoals in the North Atlantic, feeding on plankton and serving as a key forage species for larger fish, seabirds, and marine mammals.
pelagic
Balloonfish
The balloonfish is a spine-covered porcupinefish that inflates by gulping water when threatened, using its beak-like teeth to crush hard-shelled prey on tropical reefs.
reef
Asian Arowana
A large, brightly colored freshwater fish prized for its metallic scales and dragon-like appearance, native to Southeast Asian rivers and now considered endangered in the wild.
freshwater
Atlantic Flyingfish
A streamlined, silvery flyingfish of the tropical Atlantic that uses its oversized wing-like pectoral fins to glide over the surface for long distances to escape predators.
pelagic
Arctic Grayling
The Arctic grayling is a cold-water salmonid recognized by its tall, colorfully spotted dorsal fin, inhabiting clean rivers and lakes across northern North America and Siberia.
freshwater
Atlantic Halibut
The Atlantic halibut is the largest flatfish species, a right-eyed flounder with a diamond-shaped body found on cold seabeds of the North Atlantic.
saltwater
Banded Drum
A small, deep-bodied drum from the western Atlantic, distinguished by faint vertical bars crossing its silvery, high-backed body.
saltwater
Asian Swamp Eel
A slender, limbless, snake-like eel native to rice paddies and marshes of East and Southeast Asia, known for its air-breathing ability and its establishment as an introduced species in parts of the southeastern United States.
freshwater
Australian Rainbowfish
A widespread, variably colored rainbowfish found across tropical Australian and southern New Guinea waterways, ranging from olive-silver to vivid blue and yellow forms.
freshwater
Auriga Butterflyfish
A very common Indo-Pacific butterflyfish with cross-hatched white body, yellow rear, and often a trailing dorsal filament.
reef
Atlantic Salmon
An iconic anadromous fish of the North Atlantic, born in cold rivers, maturing at sea, and returning to natal streams to spawn.
freshwater
Arctic Lamprey
The Arctic lamprey is a jawless, circumpolar species found across Arctic and sub-Arctic rivers and coastal waters of North America and Asia, recognized by its sucker mouth and slender eel-like body.
brackish
Bib
The bib, or pouting, is a small, deep-bodied cod relative of the northeastern Atlantic, easily recognized by its coppery-bronze body marked with dark vertical bars.
saltwater
African Arowana
A large African bonytongue fish with a toothless, filter-feeding mouth adapted for straining plankton and detritus from floodplain waters.
freshwater
Bar Jack
A sleek, blue-green jack with a dark stripe along its back and a black-and-white striped tail, common on Caribbean and western Atlantic reefs.
reef
Atlantic Bonito
A streamlined, fast-swimming relative of tuna and mackerel, marked by dark oblique stripes running across its steel-blue back.
pelagicBeluga 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