A new species, Glossodoris tibboeli Valdes and Adams, is described based on three specimens collected from Para Island and several others observed at Para, Kahakitang, and Mahengetang Islands, north of Sulawesi, Indonesia. The species is characterized by being starkly opaque white, with a dark brown, irregular dorsal strip extending from the rhinophores to the gill. Because of the coloration and external morphology the new species is compared with members of the Glossodoris atromarginata (Cuvier, 1804) color group, from which it differs by lacking a dark line around the mantle margin. The radulae of all members of the G. atromarginata color group are similar but differ from that of the new species in lacking rachidian teeth.