Siphoviridae

bacteriophage

Siphoviridae was a family of double-stranded DNA viruses in the order Caudovirales. The family Siphoviridae and order Caudovirales have now been abolished, with the term siphovirus now used to refer to the morphology of viruses in this former family. Bacteria and archaea serve as natural hosts. The family had 1,166 species, assigned to 366 genera and 22 subfamilies. The characteristic structural features are a non-enveloped head and non-contractile tail.