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.
Balloon Molly
A selectively bred molly variety with a distinctive rounded, ball-shaped body caused by a spinal curvature, developed and maintained through aquarium breeding.
freshwater
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
Yucatan Molly
A large sailfin livebearer native to the coastal waters of the Yucatan Peninsula, known for the male's dramatically tall, sail-like dorsal fin used in courtship.
brackish
Black Molly
A solid-black, selectively bred color strain of the common molly, the black molly is one of the most recognizable and widely kept aquarium livebearers.
freshwater
Sailfin 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.
brackish
Shortfin Molly
A hardy, adaptable livebearer native to Mexico and Central America, prized in the aquarium trade for its tolerance of varied water chemistry.
freshwater
Amazon Molly
An entirely female species that reproduces through a rare cloning-like process, the Amazon molly is a biological curiosity native to rivers along the Texas-Mexico border.
freshwater
Molly Miller Blenny
A hardy little blenny that perches motionless on shallow rocks in tropical Atlantic tide pools, easily recognized by the fringed tentacles above its eyes.
saltwater
Gold Dust Molly
A selectively bred molly variety combining a golden-yellow base color with fine black speckling, developed in the aquarium trade from wild Poecilia stock.
freshwater
Balloonfish
The balloonfish is a spine-covered porcupinefish that inflates by gulping water when threatened, using its beak-like teeth to crush hard-shelled prey on tropical reefs.
reef
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
Ballan Wrasse
The largest wrasse in northern European waters, a stout rocky-reef fish with highly variable green, brown, or reddish mottling.
saltwater
Warmouth
A stocky, big-mouthed sunfish with red eyes and dark cheek streaks, at home in weedy, sluggish waters and swamps of the eastern United States.
freshwater
Long-spined Porcupinefish
The Long-spined Porcupinefish is a spiny, balloon-shaped fish that can inflate its body dramatically, erecting long, permanently attached spines as a defense against predators.
reef
Pufferfish
A slow-swimming reef fish famous for inflating its body into a spiny ball when threatened, using a fused beak-like set of teeth to feed on hard-shelled invertebrates and algae.
reef
Ocean Sunfish
The ocean sunfish is the heaviest bony fish alive, a flattened giant with no true tail that drifts through temperate and tropical seas feeding on jellyfish.
pelagic
Porcupinefish
A spine-covered, inflatable reef fish found in warm seas worldwide; nocturnal and slow-moving, it shelters in reef crevices by day and forages for hard-shelled prey at night.
reef