A drab dark brown butterfly on the upperside of wings but beautifully spangled with silvery-white bars on the underside. It is restricted to subalpine meadows above the tree-line down the wet West Coast mountains from the North-western Paparoa Range to the Haast Pass region. The flight season is relatively short, usually in February. Males fly slowly across the snow tussocks with a floppy flight like that of the tussock butterflies, retreating into the vegetation as soon as the sun is shaded. The paler females scarcely fly at all. The straw-coloured caterpillars resemble those of the black mountain ringlets more closely than the tussock butterflies - i.e. they are stout with a rounded head and the forked tail is inconspicuous.
It was discovered in 1879 by John Enys at the alpine pass at the head of the Rakaia River. Like the forest ringlet, it is the only member of the genus Erebiola. Erebiola is derived from Erebus, the ancient Greek world of darkness between Earth and Hades. The specific name 'butleri' comes from Arthur Gardiner Butler of the British Museum, who played a major part in early descriptions of some of NZ's butterflies.