Phylogenetic tree generated on a 425 bp fragment of the integrase FV gene. The tree includes all of the 17 new macaca tonkeana FV described in this study and other FV sequences from African and Asian apes and monkeys available in GenBank. The phylogeny was generated with the Neighbor-joining method, performed in the PAUP program (v4.0b10). The sequence alignment was submitted to the Modeltest program (version 3.6) to select the best model to apply to phylogenetic analyses. The selected model was the GTR+G+I one. The reliability of the inferred tree was evaluated by bootstrap analysis on 1000 replicates. Numbers at each node indicate the percentage of bootstrap samples in which the cluster to the right is supported and only values greater than 60% are shown. The branch lengths are drawn to scale with the bar indicating 0.1 nucleotide replacement per site. The tree was rooted by using the New World spider monkey Asp(SFV8spm) sequence. *= SFVpfr: (Presbytis Francoisi): despite the Asian origin of this monkey, its sequence clusters within the large African Monkey clade.