This species was first described by Arthur Gardiner Butler in 1877 using a specimen obtained from John Enys and collected in the South Island.

[5] George Francis Hampson, also mistakenly believing this was a separate species placed O. pallida in the genus Bityla.

[1] The holotype specimen of B. sericea is held at the Natural History Museum, London.

[1] Butler described the species as follows: Primaries shining greyish brown, crossed by two widely separated and slightly diverging dusky lines, the inner one in the shape of a }, the outer one composed of small lunules with whitish exterior margins; outer margin undulated, fringe silky whitish; secondaries pale brown, fringe sandy whitish; thorax greyish brown,' collar slightly darker; abdomen ?

[10] This species has been classified as having the "At Risk, Naturally Uncommon" conservation status under the New Zealand Threat Classification System.