Mormyridae
Churchill
Petrocephalus catostoma
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.
Churchill
Cichlidae
Cichlasoma portalegrensis
Cichlasoma portalegrense
Cichlidae
Cichlid
Astatotilapia tweddlei
Cichlidae
Cichlid
Australoheros guarani
Cichlidae
Cichlid
Gymnogeophagus che
Cichlidae
Cichlid
Haplochromis antleter
Cichlidae
Cichlid
Haplochromis barbarae
Cichlidae
Cichlid
Haplochromis bwathondii
Cichlidae
Cichlid
Haplochromis chilotes
Cichlidae
Cichlid
Haplochromis labiatus
Cichlidae
Cichlid
Haplochromis latifasciatus
Cichlidae
Cichlid
Haplochromis paraguiarti
Cichlidae
Cichlid
Haplochromis vanoijeni
Cichlidae
Cichlid
Paragobiocichla irvinei
Cichlidae
Cichlid
Paretroplus dambabe
Cichlidae
Cichlid
Paretroplus maromandia
Gobionidae
Cihanbeyli gudgeon
Gobio insuyanus
Cyprinidae
Cikola riffle dace
Telestes turskyi
Cichlidae
Cinderella cichlid
Teleocichla cinderella
Anostomidae
Cinnamon Headstander
Abramites eques
Nothobranchiidae
Cinnamon Killi
Fundulopanchax cinnamomeus
Loricariidae
Cinnamon Whiptail Catfish
Loricaria coximensis
Esocidae
Cisalpine Pike
Esox cisalpinus
Percidae
Citico Darter
Etheostoma sitikuense
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.