Bacilladnaviridae is a family of single-stranded DNA viruses that primarily infect diatoms.

[1][2] Similar to other eukaryotic ssDNA viruses, bacilladnaviruses are likely to replicate their genomes by the rolling-circle mechanism, initiated by the virus-encoded endonuclease (Rep).

However, the latter protein of bacilladnaviruses displays unique conserved motifs and in phylogenetic trees forms a monophyletic clade separated from other groups of ssDNA viruses.

The capsid protein of bacilladnaviruses has the jelly-roll fold and is most closely related to the corresponding proteins from members of the family Nodaviridae, which have ssRNA genomes.

[3] [4] The following genera are recognized:[5]