Cyprinidae
Dark chub
Nipponocypris temminckii
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.
Dark chub
Serrasalmidae
Dark Dusky Piranha
Serrasalmus nigricans
Cyprinidae
Dark mahseer
Naziritor chelynoides
Ariidae
dark sea catfish
Cathorops melanopus
Odontobutidae
Dark Sleeper
Odontobutis obscurus
Goodeidae
Darkedged Splitfin
Girardinichthys multiradiatus
Bryconidae
Darkfin Brycon
Brycon melanopterus
Crenuchidae
Darkfin Darter
Characidium pterostictum
Callichthyidae
Darkspotted catfish
Aspidoras fuscoguttatus
Atherinidae
Darling River hardyhead
Craterocephalus amniculus
Crenuchidae
Darter characin
Characidium fasciatum
Parodontidae
Darter characine
Apareiodon affinis
Erythrinidae
Darter Wolffish
Hoplias intermedius
Cyprinidae
Dash-dot barb
Enteromius atkinsoni
Acestrorhamphidae
Dash-dot tetra
Hemigrammus bellottii
Cyprinidae
Dashtail barb
Enteromius poechii
Characidae
Dawn tetra
Aphyocharax nattereri
Acestrorhamphidae
Dawn tetra
Hyphessobrycon eos
Cyprinidae
Day's baril
Barilius evezardi
Ariidae
Day's catfish
Nedystoma dayi
Bagridae
Day's mystus
Mystus bleekeri
Cyprinidae
Dead Sea garra
Garra ghorensis
Cyprinidae
Deccan mahseer
Tor khudree
Ritidae
Deccan rita
Rita kuturnee
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.