Search Species
Search for fish species by common or scientific name, or use filters to browse by water type, size, temperament, and difficulty.
Found 528 species
Spikey bass
Hypopterus macropterus
A small Aussie seabass with a chunky body and rows of tiny dark oval spots that show up as faint bands when the light hits right. You find it cruising sandy and seagrass shallows along Western Australia into the NT, snacking on little fish and crustaceans. Cool fish to see in the wild, but it is basically absent from the aquarium trade.
Spinaker grenadier
Ventrifossa nigrodorsalis
This is a deep-sea rattail (grenadier) from the continental slope - long, tapering body, chin barbel, and that cool dark blotch on the first dorsal fin. Its natural home is hundreds of meters down, so its needs are basically the opposite of a typical home aquarium: cold, dark, very high pressure habitat, and a life built around picking off fish and squid in the deep.
Spindle croaker
Johnius elongatus
Johnius elongatus (Spindle croaker) is a marine, demersal sciaenid from inshore waters of the western Indian Ocean (west coast of India and Sri Lanka), reported to feed on benthic worms and crustaceans; it is primarily a fisheries/food fish rather than a common aquarium species.
Spineback guitarfish
Rhinobatos irvinei
Rhinobatos irvinei is a saltwater guitarfish from the eastern Atlantic coast of Africa - basically a shark-ray mashup that cruises sandy bottoms and snuffles out crustaceans. It stays fairly "inshore" as rays go, gives live birth to a tiny litter (1-3 pups), and its low reproduction rate is a big part of why its conservation status is so serious. Not really an aquarium species unless you're talking public-aquarium-scale systems.
Spine-tailed round ray
Urotrygon caudispinosus
This is a neat little round ray from Peruvian coastal waters that hangs out on sandy bottoms and noses around for crunchy snacks. It likes to bury itself with just the eyes showing, and it does best in cooler saltwater than most reef fish. Awesome to watch, but it really belongs with keepers who can dedicate a huge, chilled tank and meaty foods.
Spiny grenadier
Coelorinchus parallelus
A deep-sea rattail with a long whip tail and spiky head ridges, it cruises 600-1000 m down around Japan, the East China Sea, and the Philippines. It even has a tiny light organ near the belly, which is wild to see in photos. Super cool fish to read about, but not one to keep at home since it wants near-freezing saltwater and deep-ocean conditions.
Spiny lanternfish
Dasyscopelus spinosus
This is a small oceanic lanternfish (family Myctophidae) found in tropical and subtropical waters of the Atlantic, Indian, and Pacific oceans. It is high-oceanic and mesopelagic/bathypelagic, becoming near-surface at night (nyctoepipelagic). Adults reach about 9 cm standard length and have spined ctenoid scales at the anal-fin base.
Spiny stargazer
Kathetostoma cubanum
This is a deepwater, bottom-hugging stargazer from the western central Atlantic that likes to sit on soft bottoms and ambush prey. Its eyes sit up on top of the head and its mouth points upward - classic stargazer vibes. Also worth knowing: sources note a venomous spine near the operculum, so this is absolutely a look-dont-touch kind of fish.
Spotfin cardinal
Jaydia queketti
This is a small marine cardinalfish from the western Indian Ocean with a really recognizable black eyespot on the first dorsal fin and a pattern of brownish spots that line up into messy stripes. It is a nocturnal zooplankton feeder that hides in rocky areas by day, then comes out after lights-out, and males mouthbrood the eggs.
Spotfin cusk
Neobythites macrops
Neobythites macrops is a deep-slope cusk-eel from the Indo-West Pacific that hangs out way down on the shelf and upper slope. It is one of those long, eel-ish bottom fish with little eyespots (ocelli) on the dorsal fin - cool camouflage/decoy stuff for life in dim water. Not really an aquarium fish in any normal sense, since it is a true deepwater marine species.
Spothead lantern fish
Diaphus metopoclampus
This is a deep-sea lanternfish with rows of photophores (little light organs) that it uses down in the dark, and it does that classic up-at-night, down-by-day vertical migration. Super cool animal, but its whole lifestyle is built around cold, high-pressure midwater life, so its not really an aquarium fish in any normal sense.
Spottail pinfish
Diplodus holbrookii
A sturdy porgy with a big inky spot at the base of the tail and a steel-blue back, spottails cruise seagrass beds picking at little crabs and other crunchy snacks. They get a lot bigger than people expect and stay busy swimmers, so they need real room. If you want a personality fish for a big salt tank, this one is fun to watch but not a beginner choice.