It is used especially in the animal kingdom. Examples:
- Introduction to Conservation Genetics, p. 371; Richard Frankham, David A. Briscoe, Jonathan D. Ballou, Cambridge University Press, 2002
- "Planctomycetes-Verrucomicrobia-Chlamydiae Superphylum: Exceptions to the bacterial definition?". Archived from the original on 17 January 2016. Retrieved 9 July 2016.