Fish Identifier

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.

all freshwater saltwater reef pelagic cartilaginous deepsea brackish

Sailfin Catfish

Sailfin Catfish

A large South American armored catfish with a tall sail-like dorsal fin, popular in aquariums and now a widespread invasive species in warm freshwater habitats worldwide.

Largetooth Sawfish

Largetooth Sawfish

One of the largest sawfish species, uniquely able to travel far up freshwater rivers, now Critically Endangered and eliminated from most of its former circumtropical range.

Blue Catfish

North America's largest catfish species, silvery-blue to slate gray with a deeply forked tail, native to the Mississippi basin and now established as an invasive predator in several Atlantic drainages.

Bighead Carp

A large, big-headed East Asian carp that filter-feeds on zooplankton, closely related to the silver carp and similarly established as an invasive species in North American rivers.

Silver Carp

A large, filter-feeding East Asian carp famous for leaping high out of the water when startled by boat noise, and notorious as an invasive species in North American rivers.

Red Lionfish

Instantly recognizable for its fan-like, striped fins and venomous spines, the red lionfish is a native Indo-Pacific reef predator that has become a damaging invasive species in the Western Atlantic.

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.

Round Goby

A bottom-dwelling goby native to the Black and Caspian Sea basins, now a widespread invasive species in the Great Lakes and parts of Europe, recognized by its fused pelvic fins and dark spot on the front dorsal fin.

Goldfish

A hardy freshwater fish domesticated from the wild Prussian carp, prized worldwide as an ornamental pond and aquarium species in many color forms.

Dwarf Pufferfish

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.

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.

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.

Least Brook Lamprey

Least Brook Lamprey

The least brook lamprey is one of the smallest lamprey species in North America, a non-parasitic freshwater fish found in small streams of the central and southeastern United States.

Botia

A genus of South and Southeast Asian freshwater loaches known for social behavior and varied patterning; the queen loach (Botia dario) is a representative species.

Dwarf Livebearer

Dwarf Livebearer

One of the smallest fish species in the world, this tiny freshwater livebearer from the southeastern United States is prized for its miniature size and easy breeding.

Sterlet

The sterlet is the smallest widespread sturgeon species, a slender freshwater fish of Ponto-Caspian rivers known for its long, thin, upturned snout with fringed barbels.

Mexican Lamprey

The Mexican lamprey is a jawless fish endemic to freshwater rivers of the central Mexican highlands, one of the few lamprey species found so far south in North America.

Discus

A round, flattened Amazonian cichlid prized for its vivid patterns and colors, considered one of the most striking freshwater aquarium fish and a demanding species to keep well.

Zebra Danio

A small, torpedo-shaped freshwater fish famous for the bold horizontal blue and gold stripes running the length of its body, and widely used as a model species in scientific research.

Masu Salmon

Masu salmon is the southernmost and westernmost Pacific salmon species, native to Japan, Korea, and the Russian Far East, notable for males that can mature and spawn entirely within freshwater.

Australian Lungfish

Australian Lungfish

One of the most primitive living fish, this large freshwater species has a single lung, paddle-like fins, and a lineage that has remained largely unchanged for over 100 million years.

Yellow Perch

A golden-yellow freshwater fish marked by dark vertical bars and orange-tinged fins, native to lakes and slow-moving rivers across North America. It is one of the most abundant and widely recognized panfish species.