Cyprinidae
Italian Barbel
Barbus plebejus
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.
Italian Barbel
Cyprinidae
Italian bleak
Alburnus albidus
Cyprinidae
Italian gudgeon
Romanogobio benacensis
Cobitidae
Italian Loach
Sabanejewia larvata
Cyprinidae
Italian riffle dace
Telestes muticellus
Cyprinidae
Italian Rudd
Scardinius hesperidicus
Cobitidae
Italian Spined Loach
Cobitis bilineata
Gobiidae
Italian spring goby
Knipowitschia punctatissima
Poeciliidae
Itapoá toothcarp
Phalloceros malabarbai
Cyprinidae
Itasenpara Bitterling
Acheilognathus longipinnis
Pseudomugilidae
Ivantsoff’s Blue-Eye
Pseudomugil ivantsoffi
Cyprinidae
Izmir chub
Petroleuciscus smyrnaeus
Cyprinidae
Izmir mminnow
Ladigesocypris mermere
Cyprinidae
Izmir nase
Chondrostoma holmwoodii
Gobionidae
Işıklı gudgeon
Gobio maeandricus
Cyprinidae
Jabal akhdar garra
Garra longipinnis
Poeciliidae
Jacareí toothcarp
Phalloceros buckupi
Cichlidae
Jack Dempsey
Rocio octofasciata
Cyprinidae
Jackson's barb
Enteromius jacksoni
Heptapteridae
Jacky
Pimelodella cristata
Petromyzontidae
Jacona Lamprey
Tetrapleurodon geminis
Loricariidae
Jacuhy pleco
Hypostomus aspilogaster
Acestrorhamphidae
Jacui Toothy
Oligosarcus jacuiensis
Cyprinidae
Jadova minnow
Delminichthys jadovensis
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.