Phylogenetic tree of coronaviruses^[1]

Phylogenetic tree of coronaviruses (content in bold/italic red font is the latest addition of newly emerged SARS-CoV-2). The phylogenetic tree showing the relationship of SARS-CoV-2 (denoted as dashed red line) to selected coronavirus is based on nucleotide sequences of the complete genome. The viruses are grouped into four genera (prototype shown): Alphacoronavirus (gray), betacoronavirus (light orange), gammacoronavirus (yellow), and deltacoronavirus (light blue). Subgroup clusters are labeled as 1a and 1b for the alphacoronavirus and 2a, 2b, 2c, and 2d for the betacoronavirus. This tree is based on the published trees of Coronaviridae and reconstructed with sequences of the complete RNA-dependent RNA polymerase-coding region of the representative novel coronaviruses.