As of September 2016, the International Union for Conservation of Nature (IUCN) lists 9131 least concern fish species. [1] 60% of all evaluated fish species are listed as least concern. The IUCN also lists 37 fish subspecies as least concern.
Of the subpopulations of fishes evaluated by the IUCN, 44 species subpopulations have been assessed as least concern.
This is a complete list of least concern fish species and subspecies evaluated by the IUCN. Species and subspecies which have least concern subpopulations (or stocks) are indicated.
Chondrichthyes includes sharks, rays, skates, and sawfish. There are 313 species and two subpopulations of cartilaginous fish assessed as least concern.
There are 148 species in the order Rajiformes assessed as least concern.
There are 79 ground shark species assessed as least concern.
There are 34 species and two subpopulations in the order Squaliformes assessed as least concern.
Species
Subpopulations
Species
There are 23 Chimaera species assessed as least concern.
There are 8759 species, 34 subspecies, and one subpopulation of ray-finned fish assessed as least concern.
Species
Subpopulations
There are 47 silverside species assessed as least concern.
There are 206 species and two subspecies of toothcarp assessed as least concern.
Species
Subspecies
Cypriniformes includes carps, minnows, loaches and relatives. There are 1231 species and three subspecies in the order Cypriniformes assessed as least concern.
Species
Subspecies
Includes sticklebacks and relatives.
Osmeriformes includes freshwater smelts and allies. There are 90 species in the order Osmeriformes assessed as least concern.
Trout-perch and its allies
There are 707 catfish species assessed as least concern.
Includes milkfish, beaked salmon and allies.
There are 3878 species and 18 subspecies in the order Perciformes assessed as least concern.
There are 74 species and seven subspecies in the order Beloniformes assessed as least concern.
Species
Subspecies
Species
Subspecies
There are 52 species in the order Synbranchiformes assessed as least concern.
There are 127 species in the order Osteoglossiformes assessed as least concern.
There are 354 species in the order Characiformes assessed as least concern.
Syngnathiformes includes the pipefishes and seahorses. There are 102 species and one subspecies in the order Syngnathiformes assessed as least concern.
Species
Subspecies
There are 143 species and one subspecies in the order Clupeiformes assessed as least concern.
Species
Subspecies
There are 175 species in the order Scorpaeniformes assessed as least concern.
There are 123 species in the order Ophidiiformes assessed as least concern.
There are 208 species and two subspecies in the order Tetraodontiformes assessed as least concern.
Species
Subspecies
There are 91 species in the order Gadiformes assessed as least concern.
There are 229 eel species assessed as least concern.
There are 167 flatfish species assessed as least concern.
There are 87 anglerfish species assessed as least concern.
There are 71 species in the order Beryciformes assessed as least concern.
There are 81 species in the order Aulopiformes assessed as least concern.
There are 141 species in the order Stomiiformes assessed as least concern.
There are 98 species in the order Myctophiformes assessed as least concern.
Cypriniformes is an order of ray-finned fish, which includes many families and genera of cyprinid fish, such as barbs, gobies, loaches, botias, and minnows. Cypriniformes is an “order-within-an-order”, placed under the superorder Ostariophysi—which is also made up of cyprinid, ostariophysin fishes. The order contains 11-12 families, over 400 genera, and more than 4,250 named species; new species are regularly described, and new genera are recognized frequently. Cyprinids are most diverse in South and Southeast Asia, but are entirely absent from Australia and South America. At 112 years old, the longest-lived cypriniform fish documented is the bigmouth buffalo.
In August 2018, the IUCN Red List of Threatened Species identified 6086 Vulnerable species, subspecies and varieties, stocks and sub-populations in the Animalia kingdom.
In the 10th edition of Systema Naturae, Carl Linnaeus described the Pisces as:
Always inhabiting the waters; are swift in their motion and voracious in their appetites. They breathe by means of gills, which are generally united by a bony arch; swim by means of radiate fins, and are mostly covered over with cartilaginous scales. Besides the parts they have in common with other animals, they are furnished with a nictitant membrane, and most of them with a swim-bladder, by the contraction or dilatation of which, they can raise or sink themselves in their element at pleasure.