Platycephalidae
Brownmargin flathead
Cociella hutchinsi
FISH SPECIES
Saltwater fish, also called marine fish, live in seas and oceans. They range from small reef residents to fast open-ocean swimmers and species that stay close to the seabed.
01 / NATURAL HISTORY
Marine fish regulate water and salts in a very different environment from freshwater fish. Body form often reflects where they live: streamlined swimmers cross open water, while compressed or camouflaged species maneuver around complex habitats.
02 / LIFESTYLE
Marine fish occupy a vast, three-dimensional environment with shifting currents, light gradients and depths. Open-water pelagic species often school to travel efficiently and confuse predators, while reef residents navigate complex crevices between foraging patches. Along the coast and continental shelves, tidal cycles and changing sunlight dictate daily peaks of activity and shelter seeking.
OBSERVATION INDEX
03 / SPECIES
Discover representative species illustrating the ecological diversity, morphologies and adaptations of this group.
Platycephalidae
Cociella hutchinsi
Opisthoproctidae
Dolichopteryx longipes
Holocentridae
Sargocentron praslin
Labrisomidae
Starksia posthon
Scyliorhinidae
Scyliorhinus garmani
Epinephelidae
Epinephelus chlorostigma
Epinephelidae
Epinephelus japonicus
Labridae
Notolabrus parilus
Haemulidae
Paranisotremus moricandi
Argentinidae
Argentina brucei
Microdesmidae
Navigobius vittatus
Syngnathidae
Leptoichthys fistularius
Synodontidae
Saurida undosquamis
Gobiidae
Sueviota bryozophila
Gobiidae
Amblygobius buanensis
Labridae
Halichoeres nigrescens
Engraulidae
Encrasicholina punctifer
Sebastidae
Sebastes exsul
Gobiidae
Gobius bucchichi
Labridae
Sparisoma radians
Pomacentridae
Chromis xutha
Heterodontidae
Heterodontus mexicanus
Cottidae
Enophrys bison
Pseudochromidae
Amsichthys knighti
04 / FIELD NOTES
Yes. Because surrounding seawater is saltier than their internal fluids, marine bony fish constantly lose water by osmosis, requiring them to drink seawater continuously and pump excess salts out via gill cells.
No. Coral reefs represent only a fraction of marine environments; the vast majority of marine species inhabit open pelagic waters, continental shelves, or the deep ocean floor.
Yes. Euryhaline and migratory species like salmon, bull sharks and European eels actively adjust their osmotic regulation between fresh and marine waters.