Koi
Koi feeding at the United States National Arboretum in Washington, D.C. Koi are ornamental varieties of domesticated common carp (Cyprinus carpio) that are kept for decorative purposes in outdoor koi ponds or water gardens. Varieties are distinguished by coloration, patterning, and scalation. Some major colors are white, black, red, yellow, blue, and cream.Photograph: Arden