Hyposmocoma tantala is a species of moth of the family Cosmopterigidae. It is known only from Mount Tantalus on Oahu.
The length of the forewings is for males and for females.[1]
The larval case is dark brown, smooth, in length and wide. Adults were reared from case-making larvae collected on bark of a damp dead tree covered partially with lichen.
The species is named tantala after Mount Tantalus, from where the type specimen was collected.