Search Species
Search for fish species by common or scientific name, or use filters to browse by water type, size, temperament, and difficulty.
Found 419 species
Southern Smiler
Opistognathus jacksoniensis
Australian jawfish found over sand/rubble near reefs where it constructs a burrow. Field references report it from ~20–30 m and often 30–50 m depths, suggesting it may be a deeper/temperate-affiliated species; aquarium care information appears limited compared to commonly kept tropical jawfishes. If attempted, provide deep mixed substrate with rubble/shell for burrow building and a tightly covered aquarium due to jumping risk.
Southwell's pipefish
Siokunichthys southwelli
A tiny tropical marine pipefish from Sri Lanka and the Philippines. Like many syngnathids, it is a slow, deliberate feeder that may require abundant small live foods and low-competition tankmates in captivity.
Spikefin goby
Discordipinna griessingeri
This is that tiny little reef goby with the crazy tall first dorsal spines and orange striping that makes it look like a living piece of candy. It spends a lot of time tucked into coral rubble and little crevices, then darts out to grab food, so giving it real hiding spots is the whole game. Also, it gets mixed up in the trade with the wrong name sometimes, so its worth double-checking the label before you buy.
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.
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.
Spotted Mandarin Dragonet (Picturesque/Psychedelic Mandarin)
Synchiropus picturatus
This little dragonet is basically a living piece of reef art-chunky fins, goofy "hovering" swimming, and those crazy psychedelic spots that look painted on. The big thing with them is they're constant pickers, cruising rockwork all day hunting tiny critters, so they're happiest in a mature tank with tons of pods (or a keeper who's ready to meet them halfway on food). If you like chill fish with tons of personality that don't bother anyone, mandarin time is hard to beat.