Heteralcis molybdantha is a moth in the Lecithoceridae family. It was described by Meyrick in 1908. It is found in Sri Lanka.
The wingspan is about 14 mm. The forewings are dark fuscous sprinkled with black, with scattered ochreous hair-scales and thick bluish-leaden-metallic subcostal and narrower submedian streaks from the base to one-third, as well as an almost straight double antemedian fascia, the first half narrow, yellow-ochreous, edged posteriorly with dark fuscous, the second half broader, bright bluish-leaden-metallic. Some irregular leaden-metallic spots are found in the disc about three-fourths and around the posterior third of the costa and termen, around the apex confluent into a streak. The hindwings are dark fuscous with a short subdorsal groove from the base, containing an expansible pencil of whitish-ochreous hairs.