Coryphellina albomarginata is a species of sea slug, an aeolid nudibranch, a marine gastropod mollusc in the family Flabellinidae.

[2] This species occurs on all coasts of New Zealand.

[3] This flabellinid nudibranch has a translucent body with a line of opaque white pigment at the edge of the foot.

The outer half of the rhinophores and oral tentacles are covered with white pigment.

A variant with lines of white pigment on the oral tentacles and rear surfaces of the rhinophores is known from northern New Zealand.