[3] It was federally listed as an endangered species of the United States in 1992.

[5] This Hawaiian lobelioid is a shrub growing 2 to 3 meters tall.

The leaves are up to 35 centimeters long by 9 wide and are lined with hard teeth.

The petals are white with purple stripes and have prickles.

[2][4] This species is threatened by habitat degradation due to feral pigs and exotic plant species such as Koster's curse (Clidemia hirta), glorybush (Tibouchina herbacea), and thimbleberry (Rubus rosifolius).