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.
Kole Tang
A compact, striped surgeonfish with a golden eye-ring, using bristle-like teeth to sweep detritus from reef rock.
reef
Ocellaris Clownfish
A small orange-and-white clownfish that lives in a mutualistic partnership with sea anemones on Indo-Pacific reefs. It is one of the most familiar reef fish species due to its bright coloring and anemone-dwelling behavior.
reef
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
Moorish Idol
An unmistakable disc-shaped reef fish with bold black-white-yellow bands and a dramatically long trailing dorsal fin.
reefJack Mackerel
A slender, schooling temperate-water jack found off southern Australia and New Zealand, identifiable by its bony lateral scutes and vital role as forage for larger ocean predators.
pelagic
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
Lemonpeel Angelfish
A small, bright yellow Pacific dwarf angelfish with a blue ring around the eye and blue edging on the fins.
reef
New Zealand Hagfish
A jawless, eel-shaped scavenger that lives on muddy seafloor around New Zealand and southeastern Australia, known for producing copious defensive slime and feeding on carcasses and invertebrates on the seabed.
saltwater
Largemouth Bass
A robust, olive-green freshwater fish with a distinctive dark lateral stripe and a very large mouth, one of North America's most popular sport fish now established worldwide.
freshwater
Muskellunge
A large, elongated predatory fish native to North American lakes and rivers, marked by dark vertical bars or spots on a lighter body. It is the largest member of the pike family and a well-known apex freshwater predator.
freshwater
Lionfish
A striking, striped reef predator native to the Indo-Pacific, now a widespread and ecologically disruptive invasive species across the Western Atlantic and Caribbean, easily recognized by its fan-like fins and venomous spines.
reef
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
Longhorn Cowfish
The Longhorn Cowfish is a boxfish encased in a rigid bony shell, instantly recognizable by the pair of long horns projecting forward above its eyes.
reef
Molly
A hardy, adaptable livebearer native to Mexico and Central America, the common molly thrives in fresh, brackish, and even marine water and is one of the most popular beginner aquarium fish.
freshwater
Leopard Bush Fish
A round-bodied Congo basin ambush predator patterned with dark leopard-like spots, prized in aquariums for its striking camouflage and air-breathing labyrinth organ.
freshwater
Maroon Clownfish
The largest and most aggressive anemonefish, with a deep maroon body and bold white or gold bars, fiercely guarding its host anemone.
reef
Leopard Shark
A slender, boldly patterned houndshark common in shallow California bays, easily recognized by its dark saddle-like blotches and spots.
cartilaginous
Megrim
A slender, left-eyed flatfish of the Northeast Atlantic and Mediterranean, valued commercially and recognizable by its thin, elongated body and large mouth.
saltwater
Least Killifish
One of the smallest vertebrates in North America, the least killifish is a tiny livebearer native to slow, vegetated wetlands of the southeastern United States despite its misleading name.
freshwater
Mummichog
A stout, hardy killifish common in salt marshes and estuaries along the North American Atlantic coast, well known for its extreme tolerance of changing salinity and oxygen levels.
brackish
Lined Seahorse
A medium-sized seahorse of the western Atlantic coast, variably colored from black to bright orange, often marked with fine pale lines on the neck and named for these subtle streaks.
saltwater
Mono Argentus
A flat, disc-shaped, mirror-silver fish with tall yellow-tinged fins, commonly seen schooling in brackish estuaries and harbors across the Indo-Pacific.
brackish
Lionhead Cichlid
Also known as the buffalohead cichlid, this Congo River rapids specialist gets its "lionhead" nickname from the rounded, maned appearance of the fatty hump on a mature male's forehead.
freshwater
Montezuma Swordtail
A Mexican livebearer notable for the male's exceptionally long, trailing sword-shaped tail extension, among the longest relative to body size of any swordtail.
freshwater
Licorice Gourami
A tiny, secretive Sumatran blackwater specialist with a dark body crossed by iridescent turquoise stripes and red-edged fins, one of several closely related "licorice gourami" species from acidic peat swamps.
freshwater
Mola Mola
The heaviest bony fish in the world, an enormous, flattened, disc-shaped giant that appears to be missing a tail, often seen basking sideways at the ocean's surface.
pelagic
Lemon Shark
A stocky, yellow-brown coastal shark named for its sandy coloration, recognized by two nearly equal-sized dorsal fins, common in shallow mangrove and reef habitats of the western Atlantic and eastern Pacific.
cartilaginous
Mudskipper
An amphibious goby that spends much of its life out of water, hopping across mudflats on muscular pectoral fins. Bulging, periscope-like eyes let it watch for predators while it hunts and defends its burrow.
brackish
Leopard Coral Grouper
A striking Indo-Pacific reef predator with a reddish-orange body densely covered in small electric-blue spots, giving it a leopard-like pattern.
reef
Marlin
A large, powerful open-ocean billfish with a long rounded spear-like bill and a tall crested back, prized as one of the ocean's fastest and most sought-after game fish.
pelagic
Leopard Wrasse
A small, strikingly patterned reef wrasse covered in a dense network of dark-edged spots, often seen hovering low over sand near coral heads while foraging for tiny invertebrates.
reef
Neon Damselfish
A small, brilliant iridescent blue damselfish with a touch of yellow on the tail, commonly seen in loose groups over rubble and coral on Indo-Pacific reefs.
reef
Longhorn Sculpin
A large, spiny-headed sculpin common on sandy and rocky seafloors along the northwest Atlantic coast, easily recognized by its oversized head and fan-like pectoral fins.
saltwater
Moon Wrasse
A fast-swimming green Indo-Pacific wrasse with pink-magenta facial streaks and a bright yellow crescent-moon tail.
reef
Longspine Snapper
The longspine snapper is a slender, bright red deepwater snapper known for an elongated filament trailing from its dorsal fin, found on steep offshore slopes across the Indo-Pacific.
deepsea
Murray River Rainbowfish
A slender, schooling rainbowfish native to Australia's Murray-Darling river system, displaying subtle pink-red stripes and yellow-tinted fins along its silvery-blue body.
freshwater
Little Tunny
A speedy, hard-fighting mackerel relative marked by distinctive wavy dark markings on its back, found in warm coastal and offshore waters of the Atlantic and Mediterranean.
pelagic
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
Lined Surgeonfish
A boldly striped blue, black, and yellow tang that fiercely defends algal-turf patches on shallow, wave-exposed reef crests across the Indo-Pacific.
reef
Marbled Hatchetfish
A tiny South American fish with a deep, keeled belly and enlarged pectoral fins that let it skim and glide just above the water surface to escape predators.
freshwater
Leafy Seadragon
An extraordinary seahorse relative covered in ornate leaf-shaped appendages, camouflaging almost perfectly among the kelp and seaweed beds of southern Australia.
reef
Naso Tang
A large surgeonfish with bright orange lips and a yellow tail-base marking, grazing algae along Indo-Pacific reef slopes.
reef
Longtail Tuna
A coastal tuna of the Indo-West Pacific with a notably slender, elongated body and a long, low second dorsal fin, often found closer to shore than other tunas.
pelagic
Neon Rainbowfish
A small, brilliantly colored rainbowfish from New Guinea whose males flash iridescent blue-violet when displaying to rivals or mates.
freshwater
Lane Snapper
A small, silvery-pink schooling snapper marked by faint yellow stripes and a black spot near the tail base, common across shallow Western Atlantic reefs and seagrass.
reef
Otocinclus
A tiny suckermouth catfish that spends most of its time grazing algae and biofilm from surfaces in slow-moving South American waters.
freshwaterLeopard Danio
A spotted color morph of the Zebrafish, the Leopard Danio trades horizontal stripes for a striking pattern of dark spots across a golden body.
freshwater
Neon Tetra
A tiny schooling characin from Amazonian blackwater streams, instantly recognized by its glowing blue-green stripe and bright red lower body, one of the most popular aquarium fish ever kept.
freshwater