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.
Walleye Pollock
Walleye pollock is an abundant, schooling cod relative of the North Pacific, identified by its slender silvery body, speckled back, protruding lower jaw, and forked tail.
pelagicWalleye
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.
freshwaterUkrainian Brook Lamprey
The Ukrainian brook lamprey is a small, non-parasitic jawless fish that lives its entire life in freshwater streams of Eastern Europe, feeding only during a long larval stage.
freshwaterKorean Lamprey
The Korean lamprey is a small, non-parasitic jawless fish native to freshwater streams of the Korean Peninsula, feeding only during a long larval stage before a brief adult life.
freshwaterYellowfin Rainbowfish
A slender rainbowfish endemic to Misool Island in Indonesia's West Papua region, named for its bright yellow unpaired fins that contrast with its silvery-olive body.
freshwaterTaimen
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.
freshwaterSohal Tang
A powerfully built surgeonfish endemic to the Red Sea and nearby Arabian waters, marked by bold blue and black striping and known for fiercely defending shallow reef flats.
reefSix Line Wrasse
The Six Line Wrasse is a small, brightly colored reef fish with six narrow orange stripes running along a purple-blue body and a black spot near the tail, often darting through coral rubble.
reefReticulated Pufferfish
A puffer of Indo-Pacific mangroves and estuaries, patterned with fine dark reticulated lines over a pale body and often marked with a network of interconnected markings resembling a map.
brackishSailfin 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.
freshwaterRed Hake
Red hake is a slender, tapering groundfish of the western North Atlantic shelf, identified by its reddish-brown color, two dorsal fins, and long thread-like pelvic fin filaments.
saltwaterRex 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.
deepseaRainbow Trout
A popular salmonid native to Pacific-drainage rivers of North America and Asia, known for its silvery body, dark spotting, and the broad pink-red stripe that gives the species its name.
freshwaterPygmy Seahorse
A tiny, near-invisible seahorse that lives its entire life camouflaged on gorgonian sea fans in the Coral Triangle, its bulbous skin tubercles mimicking the coral's polyps exactly.
reefPacific Red Snapper
A bright reddish-pink snapper of rocky reefs along the Eastern Pacific coast from Mexico to Peru, closely resembling its Atlantic namesake but found in a different ocean.
reefOrange Chromide
A small, bright orange-yellow cichlid from South Asian estuaries, marked by a single dark spot near the tail. It is the smallest member of its genus and a popular, peaceful aquarium fish.
brackishInland Silverside
A small, slender silverside native to Gulf and Atlantic coastal waters, notable for tolerating a wide range of salinities from brackish estuaries to inland reservoirs.
brackishLacustrine Rainbowfish
A brilliant turquoise-blue rainbowfish endemic to Lake Kutubu in Papua New Guinea, now considered endangered due to pollution linked to nearby natural gas extraction.
freshwaterJack Dempsey
A robust Central American cichlid named after a boxing champion for its feisty temperament, known for iridescent blue-green speckling that develops as it matures.
freshwaterKelp Bass
The kelp bass is a mottled olive-brown temperate reef fish closely tied to kelp forests along the eastern Pacific coast, often seen hovering near kelp fronds and rocky structure.
saltwaterGrenadier
Grenadiers, or rattails, are deep-sea fish found on ocean slopes worldwide, unmistakable for their oversized head tapering into a long, thin, whip-like tail with no true tail fin.
deepseaGreen Swordtail
The naturally colored, wild-type form of the swordtail, the green swordtail displays an olive-green body with a red-brown stripe and the species' signature elongated tail extension in males.
freshwaterGila Trout
The Gila trout is a rare golden-hued native trout restricted to a handful of remote headwater streams in New Mexico and Arizona, and remains one of North America's most range-limited trout species.
freshwaterEuropean Pilchard (Sardine)
A small, silvery schooling fish found along the eastern Atlantic coast and throughout the Mediterranean, forming vast shoals that graze on plankton near the surface of coastal waters.
pelagic