Fryeria bayi Bouchet, 1983 Phyllidiopsis bayi is a species of sea slug, a dorid nudibranch, a shell-less marine gastropod mollusk in the family Phyllidiidae.

[2] This species was described from 38 m depth at Point La Revellata, Punta Bianca, Corsica 42°35′02″N 8°43′41″E / 42.584°N 8.728°E / 42.584; 8.728.

[1][3] This nudibranch has a translucent white dorsum with brown flecks of pigment.

It is a small Phyllidiid, growing to 8 mm in length, although the specimens were immature and the maximum size is unknown.

[3] This species feeds on a sponge.