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.
Western Mosquitofish
Native to the Mississippi River basin and Gulf Coast, the western mosquitofish is one of the most widely introduced fish on Earth, prized and criticized in equal measure for its mosquito-control abilities.
freshwaterStriped Panchax
A larger South Asian killifish, also called the golden wonder killifish, marked by bold dark horizontal stripes on a golden-olive body. It hunts insects near the surface of ponds and rice paddies.
freshwaterWhitefish
Lake whitefish are silvery, streamlined members of the salmon family that inhabit cold, deep lakes across North America, feeding along the bottom for insect larvae and small invertebrates.
freshwaterVariable Platyfish
A close relative of the common platy, the variable platyfish is native to northeastern Mexico and shows exceptional natural variation in color and pattern, giving rise to many popular aquarium strains.
freshwaterSwordtail
Named for the elongated, sword-like extension on the male's tail fin, this energetic livebearer from Mexico and Central America is a long-standing favorite in freshwater aquariums.
freshwaterStriped Bass
A large, silvery, hard-fighting bass marked with bold black stripes, native to the Atlantic coast and now widely established in freshwater reservoirs across North America.
brackishThick-lipped Gourami
A small, hardy Myanmar labyrinth fish closely related to the Dwarf Gourami, distinguished by its noticeably thickened lips and reddish-blue diagonal banding in breeding males.
freshwaterSteel-blue Killifish
A small, brightly colored West African killifish with a metallic blue body, red spotting, and an elongated lyre-shaped tail. It inhabits swamps and forest streams in Nigeria and Cameroon.
freshwaterShort-snouted Seahorse
The short-snouted seahorse is a stocky, spiny-headed species found in coastal waters of the Mediterranean and eastern Atlantic, distinguished from its long-snouted relative by a notably short, thick snout.
saltwaterSailfin Molly
Named for the male's spectacular, sail-like dorsal fin, this coastal livebearer from the southeastern United States and Mexico is a striking sight in brackish marshes and aquariums alike.
brackishRinged Pipefish
The ringed pipefish is an alternate name for the vividly banded Dunckerocampus dactyliophorus, named for the many bold rings encircling its slender body from head to its yellow, black-spotted tail fin.
reefPumpkinseed
A small, brilliantly colored sunfish with an orange-spotted body, blue-green facial streaks, and a distinctive red spot on the black ear flap, common in weedy ponds and lakes of eastern North America.
freshwaterPollack
Pollack is a streamlined cod relative of the northeastern Atlantic, found around rocky reefs and wrecks, identified by its curved lateral line and protruding lower jaw with no barbel.
saltwaterMolly
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.
freshwaterMummichog
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.
brackishMurray 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.
freshwaterLing Cod
A large, elongated predator of the North Pacific coast known for its mottled camouflage and cavernous, tooth-filled mouth. Despite the name, it is not a true cod but a member of the greenling family.
saltwaterGuppy
A small livebearing fish native to northeastern South America, famous for the males' vividly colored, ornately shaped tails and its worldwide popularity in the aquarium hobby.
freshwaterGilthead Bream
A deep-bodied Mediterranean and Eastern Atlantic sparid named for the golden band across its forehead. A euryhaline species that moves between coastal reefs and brackish lagoons.
saltwaterFlyingfish
The common name for fish of the family Exocoetidae, known for gliding above the ocean surface on enlarged, wing-like fins; the Flyingfish (*Exocoetus volitans*) represents this widespread tropical group.
pelagicDiamond Killifish
A tiny, unusually deep-bodied killifish from Gulf Coast salt marshes, named for its compressed, diamond-shaped profile. It tolerates wide swings in salinity within tidal creeks and marsh pools.
brackishCreek Chub
A stout, adaptable minnow common in small North American creeks, the creek chub is a dominant predator in headwater streams, feeding on insects and small fish, and known for building spawning nest mounds.
freshwaterBull Trout
A large, cold-water char native to the Pacific Northwest and Rocky Mountains, requiring exceptionally cold, clean streams and listed as threatened across much of its range in the United States.
freshwaterCopperband Butterflyfish
The Copperband Butterflyfish has a silvery-white body banded in copper-orange and a long, slender snout used to probe crevices, along with a black eyespot near the tail that helps confuse predators.
reef