However, prophages closely related to PM2 are abundant in the genomes of aquatic bacteria, suggesting that the ecological importance of corticoviruses might be underestimated.

[5] The genus contains the following species:[6] Other unassigned phages:[7] The virons consist of a round, icosahedral, non-enveloped capsid of a diameter of 60 nm and an internal lipid membrane located between outer and inner protein shell.

[8] The shells are composed of three layers whose surfaces reveals a pattern with distinctive features,[9] including bush-like spikes protruding from the twelve vertices.

[citation needed] The genome is not segmented, constitutes 13% of the virus's weight and contains a single molecule of circular, supercoiled, double-stranded DNA of 10 kilobases in length.

Replication of the genome is via a rolling-circle mechanism, initiated by the virus encoded endonuclease P12.