Fifteen species of Polychaeta have been studied, two of which not identifyable to species level. Ten species are recorded from the Canary Islands for the first time. The majority of the species is distributed more or less widely in the warmer parts of the oceans, 2 are cosmopolitan. Namanereis hummelincki, thought to be endemic to West Indian fresh and brackish waters, is now recorded from Fuerteventura at the eastern side of the Atlantic Ocean.