About Notothlaspi australe Hook.f.
Notothlaspi australe (Hook.f.) is a small, prostrate perennial plant. It grows leaves that radiate from a central stem; each leaf is green to brown, has a small pointed tip, measures 3.0–6.5 mm wide, has an ovate to broadly ovate shape, and bears 1–6 teeth. Young plants initially form a single rosette, but over time they branch out to form multiple matted rosettes. It produces small white flowers, with a single flower developing from the axil of the uppermost stem. It is perennial, which distinguishes it from the related species Notothlaspi rosulatum. This species is found exclusively in the northern mountain ranges of the South Island of New Zealand, where it grows in alpine and subalpine habitats. It does not typically grow on ultramafic rock subranges such as Maungakura / Red Hill, which are instead dominated by the recently described species Notothlaspi viretum. It is one of the few species that grows in plant communities on barren alpine rock and scree fields, where it occurs alongside other species including Anistome imbricata, Dracophyllum pronum, Veronica pulvinaris, and the grass Poa colensoi.
