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.
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
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
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
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
Sockeye Salmon
A Pacific salmon renowned for its brilliant crimson spawning coloration and strong dependence on lake habitat during its freshwater juvenile stage.
freshwater
Cuban Gar
A large, endemic Cuban gar with a broad alligator-like snout, now considered vulnerable due to its restricted freshwater range on the island.
freshwater
Botia
A genus of South and Southeast Asian freshwater loaches known for social behavior and varied patterning; the queen loach (Botia dario) is a representative species.
freshwater
Mottled Sculpin
A small, mottled brown freshwater sculpin found in clear, cold streams and lakes across North America, identified by its large head, wide pectoral fins, and lack of scales.
freshwater
Mangrove Jack
A deep red Indo-Pacific snapper whose juveniles grow up in mangrove estuaries and rivers, tolerating salinities from freshwater to full seawater.
brackish
Silver Lamprey
The silver lamprey is a freshwater parasitic lamprey of central and eastern North America, recognized by its single-cusped teeth and silvery body, native to Great Lakes and Mississippi River basin drainages.
freshwater
Northern Brook Lamprey
The northern brook lamprey is a small, non-parasitic freshwater lamprey of the Great Lakes and St. Lawrence River region, believed to have evolved from a parasitic ancestor but never feeding as an adult.
freshwater
Blueback Herring
A slender, silvery anadromous herring closely related to the Alewife, distinguished by its deep blue-green back, that migrates from Atlantic coastal waters into freshwater rivers each spring to spawn.
brackish
Madtom
A small North American freshwater catfish that hides under rocks by day and carries venomous pectoral and dorsal spines used defensively when handled or threatened.
freshwater
Ocellate River Stingray
A striking South American freshwater stingray with bold eyespot-like rings across its disc, common in the Amazon and Paraná river basins and popular in the aquarium trade.
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
White Bass
A deep-bodied, silvery schooling bass with faint horizontal stripes, common in large freshwater lakes and rivers of the central United States, known for its spring spawning runs.
freshwater
Rainbow Goby
A tiny, iridescent freshwater goby whose males display shimmering blue-green and orange coloration, found clinging to rocks in fast mountain streams across the Indo-Pacific.
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
Huchen
The huchen, or Danube salmon, is Europe's largest freshwater salmonid, a powerful river predator native to the Danube basin that has become increasingly rare due to damming and habitat fragmentation.
freshwater