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.
Rachovi Killifish
A vividly colored annual killifish from coastal Mozambique, with males showing a turquoise body and a tricolor red-yellow-blue tail. It lives in temporary floodplain pools near Beira.
freshwater
Pacific Herring
A slender, silvery schooling fish closely related to the Atlantic Herring, found in cold coastal waters across the North Pacific, where it forms a critical forage base for fish, seabirds, and marine mammals.
pelagic
Mosquitofish
A small, drab livebearer native to the central and southeastern United States, the mosquitofish is famous for its voracious appetite for mosquito larvae and has been introduced worldwide for pest control.
freshwater
Poor Cod
The poor cod is a small, golden-brown Gadidae common around rocky reefs and harbors of the northeastern Atlantic and Mediterranean, identified by its short chin barbel and dark pectoral-fin blotch.
saltwater
Pacific Anchovy
A small, slender schooling fish abundant along the eastern Pacific coast from Canada to Baja California, the Pacific Anchovy is a key forage species known for its long snout and prominent silvery lateral stripe.
pelagic
Ornate Ghost Pipefish
The ornate ghost pipefish is a strikingly patterned reef fish covered in frilly skin extensions that let it blend seamlessly with crinoids and soft corals. It is one of the most photographed of the ghost pipefish species.
reefIndian Oil Sardine
A small, oil-rich pelagic fish abundant along India's western coast and the wider northern Indian Ocean, the Indian Oil Sardine forms massive schools and is one of the region's most heavily monitored fisheries species.
pelagic
Keyhole Cichlid
A calm, mild-mannered South American cichlid named for the distinctive dark keyhole-shaped blotch on its flank, this species is known for its subdued coloration and unusually peaceful temperament.
freshwater
Marble Trout
Marble trout are a large, distinctively patterned native trout of the Balkan Peninsula, named for the marbled, olive-and-brown pattern covering their body, and are now considered vulnerable due to hybridization with introduced brown trout.
freshwater
Kissing Gourami
A large, elongated Southeast Asian gourami famous for its thick, protrusible lips, which it uses to graze algae and to engage in "kissing" contests, an actual test of strength between rivals.
freshwater
Estuarine Stonefish
A heavily camouflaged, encrusted-looking fish that lies motionless on muddy estuary and mangrove bottoms across the Indo-Pacific, bearing venomous dorsal spines as a natural defense.
brackish
European Anchovy
A slender, small-bodied schooling fish with a distinctive pointed snout and underslung mouth, found in enormous shoals along European and North African coasts and throughout the Mediterranean.
pelagic
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
Demasoni Cichlid
One of the smallest mbuna cichlids, the demasoni is instantly recognizable by its bold blue-and-black barring and is known for surprisingly intense territorial aggression despite its diminutive size.
freshwater
Egg-laying Killifish
A general term for the many oviparous killifish species that scatter fertilized eggs rather than bearing live young, exemplified by the widespread blue panchax of South and Southeast Asian wetlands.
freshwater
Electric Eel
A long, air-breathing South American knifefish, not a true eel, famous for generating powerful electric discharges from specialized organs used to stun prey, navigate, and defend itself.
freshwater
Croaking Gourami
A small Southeast Asian gourami capable of producing an audible croaking sound using modified pectoral fin muscles, marked with iridescent blue-green stripes and spots along a brownish body.
freshwater
Clown Tang
A vividly striped surgeonfish with alternating blue, black, and yellow horizontal lines, one of the most aggressively territorial herbivores on shallow Indo-Pacific reef crests.
reef
Cisco
Cisco, also known as lake herring, are slender silvery relatives of whitefish that form large open-water schools in the cold lakes of the northern United States and Canada, feeding mainly on plankton.
freshwater
Catla
One of India's most important aquaculture fish, the catla is a large, fast-growing surface-feeding carp with a broad head, upturned mouth, and deep body suited to filtering plankton from open water.
freshwater
Brook Trout
A colorful char native to cold, clear streams of eastern North America, marked by worm-like back markings and red spots haloed in blue along its sides. It is highly sensitive to water quality and temperature.
freshwater
Butterfish
A disc-shaped, silvery schooling fish of the northwestern Atlantic shelf, the Butterfish migrates seasonally between inshore and offshore waters and often shelters near jellyfish as a juvenile.
pelagic
Bluehead Wrasse
A small, abundant Caribbean reef fish famous for changing color and sex as it matures, with terminal males developing a striking blue head and green body. It is one of the most numerous fish on western Atlantic reefs.
reef
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