This species was first described in 1917 by Alfred Philpott using specimens collected at Mount Cleughearn in Fiordland at around 3,250 ft and named Xanthorhoe umbrosa.

[3] In 1928 George Hudson discussed and illustrated this species under that name in his book The butterflies and moths of New Zealand.

Head, palpi, and thorax dull-greenish, tinged with ochreous and sprinkled with blackish.

Forewings triangular, costa almost straight, termen waved, bowed, oblique; dull green, ochreous-tinged; veins interruptedly outlined in black; numerous obscure irregularly-dentate fuscous transverse fasciae ; five of these fasciae, having the interspaces suffused with fuscous, form the median band, anterior margin of which is irregularly curved from 1⁄3 costa to 1⁄3 dorsum, the posterior margin, from 2⁄3 costa to 2⁄3 dorsum, has a moderate blunt double projection at middle; a black discal dot; an obscure waved pale subterminal line, suffusedly margined with fuscous anteriorly; a waved black terminal line : cilia greenish-grey, mixed and suffusedly barred with fuscous, and with a pale median line.

[3]This species is similar in appearance to Austrocidaria cedrinodes but can be distinguished as a result of its larger size.