cf./aff.

[John McNeill]

A minor addendum on "aff." and "cf."

It seems as though Barry Roth and I are in broad agreement at least as to
the relative precision of "aff." and "cf." I certainly doubt if most users
of the tag "aff." had (have?) any clear thoughts as to whether the specimen
so identified was a phylogenetically separate entity from the species with
which it was said to have affinity - if they had, they would likely have
felt able to describe it as a new species.

One small additional point that may restrain the degree of imprecision
attached to "aff." and "cf.", is the occasional occurrence of at least two
other modifiers in identifications: "sp. aff. [binomial]" and "[binomial]
var." The former clearly implies a distinct species, yet to be identified
or described, which the "aff." on its own fails to do, whereas the latter
makes clear that the specimen is NOT considered as belonging to a distinct
species, but might represent an infraspecific taxon (or merely a phenotypic
variant if "var." is thought to imply only a "variant", rather than the
formal [botanical] rank of varietas).

John McNeill