Eubranchus prietoi is a species of sea slug or nudibranch, a marine gastropod mollusc in the family Eubranchidae.

[2] This species was described from Verdicio, Asturias, Spain, 43°35′N 05°50′W / 43.583°N 5.833°W / 43.583; -5.833, in the NE Atlantic Ocean.

[1] It has been reported from Arcachon Bay, France and Senegal[3][4] as well as Ghana.

[5] Eubranchus prietoi was found with the hydroid Plumularia setacea, which is presumed to be its food.

[1] It lays short egg coils across the midrib of the hydroid.