Nuchalosyllis Rullier & Amoureux, 1979 is an extremely rare syllid genus, only known from the holotype of its type species, N. lamellicornis Rullier & Amoureux, 1979. The genus is characterized by the dorso-ventrally flattened body and the unique comb-like nuchal epaulettes. We herein describe the second specimen of this genus ever found, which is also a new species, Nuchalosyllis maiteae sp. nov.; it differs from N. lamellicornis in having different morphology of nuchal epaulettes, spinose papillae on cirrophores of dorsal cirri throughout and sub-bidentate posterior body falcigers.