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.
Arapaima
One of the largest freshwater fish in the world, this massive Amazonian species has thick armor-like scales and must surface periodically to breathe air.
freshwater
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
Mbu Pufferfish
The Mbu Pufferfish is the largest freshwater pufferfish species, native to Central Africa's Congo River system and known for its maze-like yellow body markings.
freshwater
Arowana
The arowana is a large, ancient freshwater fish of the Amazon basin, genus Osteoglossum, known for its upturned mouth, long fins, and ability to leap for surface prey.
freshwater
Striped Bass
A large, silvery, hard-fighting bass marked with bold black stripes, native to the Atlantic coast and now widely established in freshwater reservoirs across North America.
brackish
Sailfin Catfish
A large South American armored catfish with a tall sail-like dorsal fin, popular in aquariums and now a widespread invasive species in warm freshwater habitats worldwide.
freshwater
Ornate Bichir
A striking Central African freshwater fish with an eel-like body covered in an intricate leopard-spot network pattern and a row of spiny finlets along its back.
freshwater
Least Brook Lamprey
The least brook lamprey is one of the smallest lamprey species in North America, a non-parasitic freshwater fish found in small streams of the central and southeastern United States.
freshwater
Clown Loach
A brightly colored, boldly striped Indonesian freshwater fish popular in aquariums, notable for its social, playful behavior and slow growth to a surprisingly large adult size.
freshwater
Brook Silverside
A slender, nearly translucent freshwater fish of eastern North American lakes and rivers, known for its needle-like beak and habit of skipping across the water's surface.
freshwater
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
African Lungfish
An eel-like freshwater fish capable of breathing air and surviving months buried in dried mud during droughts, one of the most drought-resistant vertebrates known.
freshwater
Salmon
A large anadromous fish that hatches in freshwater rivers, migrates to the ocean to mature, and returns upriver to spawn, prized as an iconic sport fish.
freshwater
Grayling
A slender freshwater salmonid relative famed for its tall, sail-like dorsal fin, native to cold, clear rivers of Europe.
freshwater
Cherry Shrimp
A small freshwater shrimp selectively bred into a vivid cherry-red color form, popular for its algae- and detritus-grazing habits.
freshwater
Walleye
A slender, golden-olive freshwater predator named for its large, glassy, light-reflective eyes that give it excellent low-light vision for hunting at dusk and in murky water.
freshwater
Taimen
Taimen are the largest member of the salmon family, a giant freshwater predator native to remote rivers of Siberia and Mongolia that can live for decades and grow to well over a meter long.
freshwater
Prickly Sculpin
A large freshwater sculpin of Pacific coast rivers and lakes, named for the tiny prickle-like scales scattered along its sides, and among the largest members of its genus.
freshwater
Nile Tilapia
A deep-bodied African cichlid with bold stripes on its tail fin, the Nile tilapia is one of the world's most widely distributed freshwater fish through aquaculture and introductions.
freshwater
Kokanee Salmon
Kokanee are a landlocked, non-migratory form of sockeye salmon that spend their entire life in freshwater lakes, turning bright red during their autumn spawning run into tributary streams.
freshwater
Cardinal Tetra
A tiny, jewel-toned freshwater fish with an iridescent blue stripe running the length of its body above a vivid red stripe below, native to the blackwater tributaries of the Amazon.
freshwater
Brook Lamprey
The brook lamprey is a small, non-parasitic freshwater lamprey of Pacific Northwest streams that never feeds as an adult, spending most of its life buried as a filter-feeding larva.
freshwater
Blackstripe Topminnow
A slender freshwater killifish of the central and eastern U.S., identified by a single solid black stripe running from snout to tail. It inhabits quiet pools and slow stream reaches.
freshwater
Black Ghost Knifefish
A uniformly black, blade-shaped freshwater fish that swims using a long undulating ventral fin and navigates using a weak electric field generated along its body.
freshwater