Fish Scientific Name: Why There Is None, Plus 20 Examples

There is no single scientific name that covers every fish. Older reference works grouped all fish in a class called Pisces, but Wikipedia notes that this class is no longer used in formal classification.

The reason is evolutionary. Land vertebrates (tetrapods, including humans) descend from bony fish, so any natural group that contains all bony fish, or all jawed fish, also contains the tetrapods. Biologists call a group like 'fish' paraphyletic: Wikipedia's Fish article defines fish as all vertebrates except the tetrapods. So 'fish' is still a useful everyday and scientific word, but it is not one taxon with one Latin name.

What you usually want instead is either the name of a fish group (for example Chondrichthyes for sharks and rays) or the two-part name of a single species (for example Cyprinus carpio for the common carp). Both are below.

Species counts are from Wikipedia's Fish article.

• Jawless fish, Agnatha or Cyclostomi: hagfish and lampreys, 118 species. See our jawless fish page.
• Cartilaginous fish, Chondrichthyes: sharks, rays and chimaeras, over 1,100 species. See cartilaginous fish.
• Bony fish, Osteichthyes: everything else, split into two classes.
• Ray-finned fish, Actinopterygii: over 32,000 species; the teleosts within it make up about 96% of all living fish.
• Lobe-finned fish, Sarcopterygii: among fish, only the coelacanths (2 species) and lungfish (6 species) survive. See coelacanth and bony fish.

Each name links to a page that shows how to identify that fish.

• Largemouth bass: Micropterus salmoides (page)
• Smallmouth bass: Micropterus dolomieu (page)
• Bluegill: Lepomis macrochirus (page)
• Rainbow trout: Oncorhynchus mykiss (page)
• Brown trout: Salmo trutta (page)
• Walleye: Sander vitreus (page)
• Northern pike: Esox lucius (page)
• Channel catfish: Ictalurus punctatus (page)
• Common carp: Cyprinus carpio (page)
• Goldfish: Carassius auratus (page)
• Striped bass: Morone saxatilis (page)
• Red drum: Sciaenops ocellatus (page)
• Alligator gar: Atractosteus spatula (page)
• Bowfin: Amia calva (page)
• Ocean sunfish: Mola mola (page)
• Betta: Betta splendens (page)
• Ocellaris clownfish: Amphiprion ocellaris (page)
• Oscar: Astronotus ocellatus (page)
• Freshwater angelfish: Pterophyllum scalare (page)
• Whale shark: Rhincodon typus (page)

The smallest fish in Wikipedia's Fish article, Paedocypris progenetica, is about 8 mm long; see smallest fish.

Every species name follows binomial nomenclature, which Wikipedia describes this way:

• Two parts: the genus, then the specific epithet. In Micropterus salmoides, Micropterus is the genus of black basses and salmoides picks out the largemouth.
• Capitals: the genus always starts with a capital; the second part never does, even when it comes from a person's or place's name.
• Italics: both parts are italicised in print.
• Starting point for animals: 1758, the 10th edition of Linnaeus's Systema Naturae (plants start from 1753).
• Author and year: zoologists may add the name of the person who described the species and the year, as in 'Linnaeus, 1758'. When that author and year sit in parentheses, the species has since been moved to a different genus from the one it was first described in.

A practical tip: the genus tells you the close relatives. Two fish sharing Micropterus are both black basses; two sharing Lepomis are both true sunfish.

Scientific names exist because common names are unreliable:

• One name, many fish: 'bream' and 'perch' each mean different fish in different countries; see our pages on bream and perch.
• One fish, many names: FishBase lists 306,369 common names in 344 languages, and 94,647 synonyms (older or replaced scientific names) for its 33,230 species. Its statistics page says these figures are as of October 2015, so the live database is larger.
• Names change: because of synonyms, a name in an old field guide may no longer be the accepted one. Search the name in FishBase and it shows the currently accepted name.

The word 'fish' itself has a grammar rule worth knowing. Wikipedia notes that 'fish' is the plural for many individuals of one species, while 'fishes' refers to several species.

If you have the fish but not its name, a photo is the fastest start. FishLens identifies a fish from a photo and shows the scientific name with the common name. Treat the result as a lead, not a final answer: check the fin and mouth features listed on the species page, then confirm the accepted name in FishBase. Our guide to identifying a fish from a photo explains which angles to shoot.

Research and drafting for this page were assisted by AI and checked line by line against the sources listed below. Every number names the organisation it comes from, and where sources disagree we say so instead of picking one silently. Prices and rules are given with the date we checked them; they change, so confirm before you rely on them. If you find an error, tell us and we will correct it.