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.
Gambusia
A small, hardy North American livebearer famous for its voracious appetite for mosquito larvae, widely introduced worldwide for mosquito control with significant ecological consequences.
freshwater
Butterfly Splitfin
A striking Mexican livebearer known for its black body, yellow-orange tail band, and unusual reproductive biology shared with other goodeids.
freshwater
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
Redtail Splitfin
A colorful Mexican goodeid livebearer, with males showing a vivid orange-red tail band contrasting a steel-blue body, popular in the aquarium trade.
freshwater
Platy
A small, compact livebearer native to Mexico and Central America, the platy is prized for its bright colors, peaceful nature, and ease of breeding in home aquariums.
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
Southern Platyfish
The full common name for the widely kept platy, the southern platyfish is a small, hardy livebearer native to Mexico, Belize, and Guatemala, prized for its color variety and easy breeding.
freshwater
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
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
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
Alligator Gar
A massive, armor-scaled freshwater fish with a broad alligator-like snout lined with two rows of sharp teeth, among the largest freshwater fish in North America.
freshwater
Tomcod
The Atlantic tomcod is a small, estuarine member of the cod family found along the northwestern Atlantic coast, notable for tolerating brackish and nearly fresh water unlike most of its relatives.
brackish
Gulf Pipefish
The Gulf pipefish is a small, slender pipefish common in seagrass beds and estuaries around the Gulf of Mexico and southeastern United States, notable for tolerating salinities ranging from full seawater to nearly fresh water.
brackish
Iridescent Shark
Despite its name, this is a large freshwater catfish, not a shark, recognized in juveniles by an iridescent sheen and dark stripes that fade with age.
freshwater
Electric Catfish
An African freshwater catfish capable of generating strong electric discharges from specialized body tissue used for hunting and defense.
freshwater
Goldfish
A hardy freshwater fish domesticated from the wild Prussian carp, prized worldwide as an ornamental pond and aquarium species in many color forms.
freshwater
Common Roach
A widespread European freshwater fish with a silvery body and distinctive red-orange fins, forming large shoals in slow rivers, lakes, and canals.
freshwater
Betta
A small, vividly colored Southeast Asian freshwater fish famed for its flowing fins and the intense territorial aggression of males toward rivals.
freshwater
Dwarf Pufferfish
The Dwarf Pufferfish is one of the world's smallest puffers, a freshwater species from southern India prized for its tiny size and expressive, alert behavior.
freshwater
Arapaima
One of the largest freshwater fish in the world, this massive Amazonian species has thick armor-like scales and must surface periodically to breathe air.
freshwater
Ember Tetra
A tiny, glowing orange-red tetra that shoals in large numbers and is among the smallest characins kept in freshwater aquaria.
freshwater
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
Arowana
The arowana is a large, ancient freshwater fish of the Amazon basin, genus Osteoglossum, known for its upturned mouth, long fins, and ability to leap for surface prey.
freshwater
Striped 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.
brackish