[1] It is endemic to New Zealand and collected at Aoraki / Mount Cook.

This species was first described by Alfred Philpott in 1924, collected by Dr. R. J. Tillyard on Aoraki / Mount Cook at 2,500 ft in March, and named Simaethis tillyardi.

[3] George Hudson discussed and illustrated this species in his 1928 publication The butterflies and moths of New Zealand.

Legs whitish mixed with bronzy-fuscous, apices of tibiae and tarsi annulated with white.

Forewings moderate, costa hardly arched, apex pointed, termen markedly sinuate, oblique; pale bronzy-fuscous mixed with dark fuscous; markings snow-white; a small basal patch; a broad band before middle, projecting outwardly in disc and touching following band; an outwardly - oblique fascia from costa beyond middle, coalescing in disc with broad band at ¼ and terminating on tornus; a terminal band, dilated at apex; in the dark-fuscous discal area and above dorsum at ¾ are a few shining steel-blue scales: fringes on termen pale bronzy - fuscous with three white lines, on costa darker fuscous, with median white line.