Trinchesia macquariensis is a species of sea slug, an aeolid nudibranch, a marine gastropod mollusc in the family Trinchesiidae.
The adult size of this species is up to 5 mm in length.
This species was described from Buckles Bay, Macquarie Island, 54°29′49″S 158°56′07″E / 54.4969°S 158.9353°E / -54.4969; 158.9353.
