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.
Seahorse
An unmistakable upright-swimming fish with a horse-like head and curled prehensile tail, notable for males carrying and giving birth to offspring.
reef
Peacock Blenny
A shallow-water Mediterranean blenny in which breeding males grow a tall fleshy head crest and a bold eyespot on the dorsal fin.
saltwater
Rainbow Wrasse
A slender Mediterranean and eastern-Atlantic wrasse; terminal males have a vivid orange zigzag stripe along a blue-green body.
saltwater
Bleeding Heart Tetra
A deep-bodied upper Amazon characin marked by a small red 'bleeding heart' spot and, in males, a dramatic elongated dorsal fin.
freshwater
Ribbon Eel
The Ribbon Eel is a slender, brightly colored moray that changes from a black juvenile to a blue male to a yellow female over its lifetime while anchored in a sand burrow.
reefPouched Lamprey
The pouched lamprey is a jawless, eel-shaped fish named for the fleshy throat pouch that develops in breeding males, migrating from the open ocean into Southern Hemisphere rivers to spawn.
brackish
Green 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.
freshwater
Rainbow Killifish
A vividly patterned annual killifish from Mozambique's seasonal floodplain pools, with males displaying a rainbow of red, blue and orange scale colors.
freshwater
Red Rainbowfish
A striking, deep-bodied rainbowfish endemic to Lake Sentani in Papua, New Guinea, with adult males turning an intense salmon-red as they mature.
freshwater
Northern Studfish
A large, robust topminnow of clear, rocky streams in the Ozark and Appalachian interior highlands, with males showing rows of iridescent blue-green spots.
freshwater
Dwarf Neon Rainbowfish
A pint-sized New Guinea rainbowfish and one of the smallest Melanotaenia species, known in the aquarium trade for its saturated blue-violet males.
freshwater
Emerald Rainbowfish
A deep-bodied rainbowfish endemic to Lake Wanam in Papua New Guinea, with mature males displaying a brilliant iridescent emerald-green sheen.
freshwater
Common Dragonet
A sand-dwelling northeastern Atlantic fish with striking sexual dimorphism, males growing a dramatically elongated dorsal fin and long tail streamers.
saltwater
Wrestling Halfbeak
Named for the ritualized jaw-locking contests between rival males, the wrestling halfbeak is a slender surface-dwelling fish from Southeast Asian creeks and mangrove-fringed brackish waters.
brackish
Palon Killifish
A small East African annual killifish in the genus Nothobranchius, with males displaying coppery orange-red coloring and blue speckling. It inhabits temporary coastal pools tied to seasonal rains.
freshwater
Pearl Gourami
A peaceful Southeast Asian labyrinth fish prized for its lace-like pearly pattern and a black stripe running from snout to tail, with males showing an orange throat and breast.
freshwater
Golden Topminnow
A small southeastern U.S. killifish whose males show golden-yellow coloring with iridescent blue-green spotting. It favors quiet, well-vegetated ponds, swamps, and slow backwaters.
freshwater
California Sheephead
A large sequential-hermaphrodite wrasse of California and Baja kelp forests, with males showing a striking black-and-red pattern and prominent canine teeth used to crush hard-shelled prey.
reef
Twinspot Wrasse
A large Indo-Pacific wrasse; juveniles are white with two red-and-black spots, while old males become bulky and greenish with a forehead hump.
reef
Lake Wanam Rainbowfish
A deep-bodied rainbowfish endemic to the small crater Lake Wanam in Papua New Guinea, with males showing rich orange-red body coloration.
freshwater
Emperor Tetra
A refined, violet-blue tetra from Colombia known for a bold black lateral stripe and males' elongated, sword-like central tail rays.
freshwater
Endler's Livebearer
A tiny, dazzlingly colorful relative of the guppy discovered in a handful of Venezuelan lagoons, the Endler's livebearer is prized by aquarists for its metallic, jewel-toned males.
freshwater
Dwarf Gourami
A small, colorful labyrinth fish from South Asia, with males displaying vivid diagonal red and blue stripes, popular in the freshwater aquarium trade.
freshwater
Congo Tetra
A large, iridescent tetra from the Congo River basin, with shimmering blue-violet-gold flanks and, in males, a distinctive flowing, frayed tail fin.
freshwater