Atha is a monotypic moth genus in the family Oecophoridae. Its only species, Atha trimacula, is found in Chile. Both the genus and species were described by John Frederick Gates Clarke in 1978.[1]
The wingspan is about 16 mm. The forewings are light buff overlaid with greyish fuscous, largely obscuring the lighter ground colour. There is a conspicuous, outwardly oblique, fuscous spot at the basal two-fifths, in the cell and there is a similar longitudinal blotch on the fold at the basal two-fifths. Across the end of the cell is an oblique fuscous spot. The hindwings are light greyish fuscous, paler basally.[2]