This article lists fish commonly kept in aquariums and ponds. [1]
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.
As of 19 August 2018, the IUCN Red List of Threatened Species has identified 3,005 critically endangered species, subspecies, stocks and subpopulations in the Animalia kingdom.
On 19 August 2018, the IUCN Red List of Threatened Species identified 4584 endangered species, subspecies, stocks and subpopulations.
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.