This species was first described by Alfred Philpott in 1930, using specimens collected on the slopes of Mount Ruapehu at Tongariro National Park in January, and named Simaethis inspoliata.

[2] The male holotype specimen is held at the Auckland War Memorial Museum.

Forewings with costa moderately arched, apex rounded, termen hardly rounded, oblique; deep blackish fuscous densely sprinkled with bluish white scales which tend to form fasciae at base, 1⁄3 and 3⁄4 ; a short streak of whitish scales along termen above tornus; usually a rather conspicuous white spot on costa at 3⁄4; fringes dark drown, tipped with white at tornus and beneath apex.

Hindwings dark purplish fuscous; a very obscure whitish fascia from tornus to about middle of wing, sometimes absent: fringes brown, more or less mixed with white and with a broad purplish fuscous basal band.

[4] This species is endemic to New Zealand and has been observed in Tongariro National Park.