Bagridae
False black lancer
Bagrichthys obscurus
FISH SPECIES
Freshwater Fish
Freshwater fish spend all or part of their lives in rivers, lakes, streams and wetlands. The label describes an environment, not one branch of the fish family tree, so freshwater species include many unrelated shapes and lineages.
FISH ATLAS / FIELD GUIDEFreshwater FishIN THIS CHAPTER01 / Characteristics02 / Lifestyle03 / Species04 / Field notes
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01 / NATURAL HISTORY
Characteristics
Freshwater habitats contain far less salt than seawater and can change quickly with seasons, floods and drought. Fish living there use many different strategies, from streamlined bodies for current to barbels that help find food near the bottom.
- 01River fish
- 02Lake fish
- 03Stream fish
02 / LIFESTYLE
Lifestyle
Life in freshwater follows the movement of water and food. Some fish hold position in a current and intercept drifting prey; others search plants or sediment for a meal. Changes in flow and water level can open feeding grounds or trigger movements toward spawning areas. These behaviors reflect how fish balance hydrodynamic energy expenditure against food intake.
OBSERVATION INDEX
- Holding position in a current
- Feeding among plants or sediment
- Movement with changing water levels
03 / SPECIES
Representative species
Discover representative species illustrating the ecological diversity, morphologies and adaptations of this group.
False black lancer
Acestrorhamphidae
False black tetra
Gymnocorymbus thayeri
Callichthyidae
False blochi catfish
Corydoras delphax
Gobiidae
False Celebius Goby
Glossogobius illimis
Cichlidae
False firemouth cichlid
Cribroheros robertsoni
Auchenipteridae
false jaguar catfish
Liosomadoras morrowi
Nothobranchiidae
False jewel killi
Aphyosemion exigoideum
Callichthyidae
False macropterus
Aspidoras albater
Potamotrygonidae
False Reticulate Freshwater Stingray
Potamotrygon humerosa
Acestrorhamphidae
False rummynose tetra
Petitella georgiae
Characidae
false silver tetra
Tetragonopterus chalceus
Cyprinidae
False Spanner Barb
Barbodes kuchingensis
Callichthyidae
false spotted catfish
Corydoras leucomelas
Gymnotidae
False Tiger Knifefish
Gymnotus javari
Acestrorhamphidae
False X-Ray Tetra
Hyphessobrycon simulatus
Plotosidae
False-spined catfish
Neosilurus pseudospinosus
Cyprinidae
Fang's Puffer
Pao fangi
Lebiasinidae
Fanning pyrrhulina
Pyrrhulina rachoviana
Percidae
Fantail darter
Etheostoma flabellare
Petromyzontidae
Far Eastern brook lamprey
Lethenteron reissneri
Trichomycteridae
Fat catfish
Rhizosomichthys totae
Cyprinidae
Fat fish
Sinocrossocheilus bamaensis
Cichlidae
Fat Oscar
Astronotus crassipinnis
Cyprinidae
Fat spring minnow
Pseudophoxinus crassus
04 / FIELD NOTES
A closer look
What makes a fish freshwater?
It is recorded from inland waters with low salinity for all or part of its life cycle.
Are all freshwater fish closely related?
No. Freshwater is a habitat category that includes many separate evolutionary groups.
Can freshwater fish survive in seawater?
Most cannot; without physiological adaptations to excrete excess salt, their cells rapidly lose water through osmosis and dehydrate in hypertonic seawater.