Circumscription
The distinction between Stachys and other genera is unclear and has varied from one author to another. In 2002, a molecular phylogenetic study showed that Stachys officinalis is not closely related to the rest of the genus. This study also found six other genera to be embedded within Stachys as it is currently circumscribed. The embedded genera are Prasium, Phlomidoschema, Sideritis, Haplostachys, Phyllostegia, and Stenogyne.
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