Apogonidae
Blackvent cardinalfish
Ostorhinchus melanoproctus
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.
Apogonidae
Ostorhinchus melanoproctus
Monacanthidae
Thamnaconus melanoproctes
Chaetodontidae
Chaetodon falcula
Exocoetidae
Hirundichthys marginatus
Alepocephalidae
Alepocephalus blanfordii
Labridae
Polylepion cruentum
Dorosomatidae
Amblygaster clupeoides
Pomacentridae
Chrysiptera bleekeri
Bothidae
Engyprosopon bleekeri
Cirrhitidae
Cirrhitichthys bleekeri
Scorpaenidae
Ebosia bleekeri
Labridae
Chlorurus bleekeri
Congridae
Bathycongrus bleekeri
Dinematichthyidae
Beaglichthys bleekeri
Labridae
Halichoeres bleekeri
Labridae
Iniistius naevus
Narkidae
Typhlonarke aysoni
Gobiidae
Typhlogobius californiensis
Narcinidae
Benthobatis marcida
Microdesmidae
Microdesmus luscus
Dinematichthyidae
Dactylosurculus gomoni
Ophichthidae
Callechelys papulosa
Psychrolutidae
Psychrolutes phrictus
Psychrolutidae
Psychrolutes marcidus
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.