The Tetraviridae were a family of viruses so named because they have a T=4 symmetry (T is the triangulation number), are extremely host specific, and infect moths and butterflies of the following genera: The Tetraviridae were a family of viruses so named because they have a T=4 symmetry (T is the triangulation number), are extremely host specific, and infect moths and butterflies of the following genera: This family was divided into three families by the ICTV in 2011: Alphatetraviridae, Carmotetraviridae and Permutotetraviridae.