Thorunna punicea is a species of sea slug, a dorid nudibranch, a shell-less marine gastropod mollusk in the family Chromodorididae.
This species was described from Passe de Koumac, New Caledonia, .
This species is similar in coloration to Hypselodoris melanesica and Mexichromis albofimbria. It has a purple mantle with a thin white margin and darker purple bases to the rhinophores and gills.