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.[4] In 1988 John S. Dugdale placed this species in the genus Austrocidaria.[2] The male holotype specimen is held at the New Zealand Arthropod Collection.[2]
Description
Male holotype specimen.
Philpott described this species as follows:
♂♀. 33-40 mm. Head, palpi, and thorax dull-greenish, tinged with ochreous and sprinkled with blackish. Antennae moderately bipectinated, brownish-ochreous. Abdomen ochreous-grey with paired black dorsal dots on each segment. 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. Hindwings with termen rounded, crenate; greenish-grey; the markings of the forewings faintly reproduced but less curved and dentate; a prominent black crenate terminal line : cilia as in forewings. Undersides grey, with fuscous markings of upper sides clearly shown.[3]
This species is similar in appearance to Austrocidaria cedrinodes but can be distinguished as a result of its larger size.[3]
Distribution
A. umbrosa is endemic to New Zealand.[1] This species has been observed only in the South Island, in Fiordland.[4][5][6][7]
Behaviour
D. longifolium.
Adults of this species have been recorded as being on the wing in December, January and March.[4][8] They are nocturnal and have an affinity for Dracophyllum longifolium.[4]
