[1][2][3][4] The family name, Halspiviridae, is derived from halophilic and spindle-shaped, in reference to the habitat and virion morphology, respectively.

[1] The virion has a spindle-shaped morphology and is similar in shape to that of viruses infecting thermophilic archaea, the Fuselloviridae, and His1 was originally described as a probable member of that group.

[1] However, it was later found that there is no genetic relationship and their replication strategies are entirely different, and so His1 was classified into a new group, genus Salterprovirus within the family Halspiviridae.

[citation needed] Environmental DNA sequences derived from Namib salt pans indicate the presence of currently unrecognised, distant relatives of His1.

There is some variation in particle length (e.g. example seen left of centre), but most display the typical limoniform capsid with a short tail.