Critically Imperiled (NatureServe)
Forbes & Lydgate
Viola helenae is a rare species of flowering plant in the violet family known by the common name Wahiawa stream violet. It is endemic to Hawaii, where it is known only from the Wahiawa Mountains of Kauai. It is threatened by exotic plant species and feral pigs. It is a federally listed endangered species of the United States.
This species is in decline and its numbers have dropped since the 1990s. There are two populations left, one of which was decimated by a landslide in 2005, leaving only a few seedlings and a seed pod. The other population, containing seven individuals, may be sterile and is too far from the first population to interbreed with it.