Dichomeris orthacma is a moth in the family Gelechiidae. It was described by Edward Meyrick in 1926. It is found in South Africa.[1]
The wingspan is about 13 mm. The forewings are white irregularly sprinkled with fuscous and with a rather broad fuscous median streak from the base to the apex, the upper edge mixed with dark fuscous. There is a black dot on the fold beneath the middle of the wing and a marginal series of black dots on the apical part of the costa and termen. The hindwings are whitish grey.[2]