Knud Rahn gave the species its current name in 1996, based on Joseph Dalton Hooker's original description (as P. uniflora) in 1854.

Plants of this species of plantain are perennial with a rosette habit, with narrowly angular-ovate leaves with few (less than 10) teeth, and numerous angular or rounded seeds.

[3] It was originally described by British botanist Joseph Dalton Hooker as Plantago uniflora in 1854,[2] which was an illegitimate name due to another plant previously described by Carl Linneaus already having that name.

[1] The holotype was collected by William Colenso from the Ruahine mountains, North Island, New Zealand.

[4] Plantago unibracteata plants are small rosettes with a primary root up to 10 mm thick, with up to 34 usually narrowly angular-ovate leaves, and with visible, short (<13 mm long), rust-coloured leaf axillary hairs in the basal rosette.

[4] It is found on exposed ridges, herbfields and grasslands in bogs, on the edges of streams and tarns, in damp or wet areas, from 440 to 1830 m above sea level.

[9] Similarly, Plantago unibracteata was closely related to P. triandra in a phylogenetic study of the New Zealand species using amplified fragment length polymorphisms (AFLPs).

It was hypothesized that decaploid and dodecaploid P. unibracteata are allopolyploids that have evolved multiple times from octoploid P. triandra and another species.