Cichlidae
Green cichlid
Herichthys pratinus
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
SCROLL
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.
Green cichlid
Cichlidae
Green Discus
Symphysodon tarzoo
Crenuchidae
Green dwarf tetra
Odontocharacidium aphanes
Balitoridae
Green Gecko Loach
Homalopteroides smithi
Balitoridae
Green Gecko Loach
Homalopteroides tweediei
Callichthyidae
green gold catfish
Corydoras melanotaenia
Cichlidae
Green happy
Sargochromis codringtonii
Cyprinidae
Green Labeo
Labeo fisheri
Acestrorhamphidae
green neon tetra
Paracheirodon simulans
Serrasalmidae
Green Pacu
Utiaritichthys longidorsalis
Loricariidae
Green Pixy Catfish
Hisonotus aky
Rivulidae
Green rivulus
Rivulus cylindraceus
Cichlidae
Green Severum Cichlid
Heros efasciatus
Catostomidae
Green Sucker
Pantosteus virescens
Centrarchidae
Green Sunfish
Lepomis cyanellus
Cichlidae
Green terror
Andinoacara rivulatus
Acestrorhynchidae
Green Tetra
Heterocharax macrolepis
Salmonidae
Green trout
Salmo viridis
Erythrinidae
Green Wolffish
Hoplias mbigua
Loricariidae
Green's Bristlenose Catfish
Ancistrus greeni
Percidae
Greenbreast darter
Etheostoma jordani
Osphronemidae
Greeneyed Betta
Betta livida
Cichlidae
Greenface Aulonocara
Aulonocara saulosi
Cichlidae
Greenface Sandsifter
Lethrinops furcifer
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.