The species is named for the renowned nudibranch taxonomist Dr. Richard C. Willan.

This nudibranch is found in the Western Pacific Ocean, from Indonesia and the Philippines to Vanuatu.

This species can be distinguished by the very prominent white specks found on the gills and rhinophores.

[3] Individuals in this species can range in color from dark blue to a translucent white.

It has been reported to eat Cacospongia mycofijiensis and Semitaspongia, both in the family Thorectidae.