Old Blue False Pennyroyal (Hedeoma pilosa)
This species was a perennial herb that formed mats about 4 cm high.
The Old Blue False Pennyroyal is known exclusively from a single specimen that was collected (apparently in 1940) at a limestone overhang in the Glass Mountains in Brewster County in western Texas, USA.
The species was not recorded since and probably is extinct.
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edited: 12.04.2019