Also known as: Entrez Taxonomy Page

"The NCBI taxonomy database contains the names of all organisms that are represented in the genetic databases with at least one nucleotide or protein sequence.""”Homepage. Searches provide links to genetic data sets and other information specific to a species or taxa group. Click on the "Taxonomy Resources" link to find a list of additional resources arranged by broad groups such as "Fungi" or "Viruses."

http://www.ncbi.nlm.nih.gov/sites/entrez?db=taxonomy