This taxon name is not current. The available references for this name are:
Isopogon drummondii Benth. is more recently known as Isopogon autumnalis Rye & T.Macfarlane
Reason See B.L. Rye & T.D. Macfarlane in Nuytsia 30:310 (2019)
See also: A longer explanation of these and other terms in our Plant Names Primer.
A taxon name that is no longer current will retain its ‘Threatened’, ‘Extinct’, or ‘Extinct in the Wild’ status until a new name has been published in a Biodiversity Conservation Order.