Reconstructed nectin3 proteins from CrocERV31 and a simplified diagram of the provirus. Maximum Likelihood phylogenies and sequence alignments were created from the reconstructed nectin3 proteins encoded by one lineage within CrocERV31. ERV IDs are provided within the tree and the alignment (see also Additional file 8). ‘Amis’ stands for A. mississippiensis and ‘Asin’ for A. sinensis. Shaded columns indicate the positions of indels within the alignment. Numbers within the tree indicate statistical support for the branches and the scale bars indicate branch length. Proviral structure is not to scale.