Unrooted phylogenetic tree of the translated amino acid sequences of all 218 vsp genes with complete sequences. Full length vsp proteins were aligned, the alignment manually corrected, and an unrooted tree produced. Predominate clades are listed as I, II, and III and colored Green, Blue and Red. Many of the 218 vsp names are not shown on this tree due to confined space at the ends of the branch points. Representative members of each clade are shown. The bar at the bottom of the figure signifies branch length related to number of substitutions per residue analyzed.