On basis of 2 specimens, collected from the continental shelf of Zumaia, Guipúzcoa (Spain), the species
Palposyllis prosostoma Hartmann-Schröder, 1977 is cited for first time to the Iberian fauna. The specimens are described, including some important anatomic and taxonomic aportations; also, the validity of the genus
Palposyllis, only known by its original description and composed by only one known species, is discussed. A new diagnosis to
Palposyllis is proposed.