Thymistadopsis undulifera is a moth in the family Drepanidae.

Adults are whitish, suffused with very pale ferruginous, the forewings with crenulated (scalloped) ferruginous antemedial and postmedial lines, the latter very acutely angled below the costa, then oblique.

There are dark points at the angles of the cell.

The hindwings have a very slight ferruginous tinge and a fine postmedial line from the submedian fold to the inner margin.

This article on a moth of the subfamily Drepaninae is a stub.