Frank Reichenbacher schreef
I am looking for a single volume synopsis of plant systematics for the
world. Cronquist '68 was limited to flowering plants, I would like
everything in Plantae. Mabberley, as you are aware, is nothing at all like
the old Cronquist book.

That took you awhile to be precise. However put like that the question is
easy. The latest work to contain all the species of Plantae of the world (as
then known) is the Species Plantarum. It is reprinted regularly.
PvR

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