25.1. For nomenclatural purposes, a species or any taxon below the rank of species is regarded as the sum of its subordinate taxa, if any. In fungi, a holomorph also includes its correlated form-taxa (see Art. 59).
Ex. 1. When Montia parvifolia (DC.) Greene is treated
as comprising two subspecies, one must write M. parvifolia
subsp. parvifolia for that part of the species that includes
the nomenclatural type and excludes the type of the name of the
other subspecies, M. parvifolia subsp. flagellaris
(Bong.) Ferris. The name M. parvifolia applies to the species
in its entirety.