Key for identification of Abrolhos species of Polycirrus
1 Notochaetae one type (pinnate), nephridial papillae on segments 3–11, first neurochaetae on segment 7 ..................................................... Polycirrus abrolhensis new species
Notochaetae two types (pinnate and smooth), first neurochaetae on segment 11 .......... ......................................................................................... Polycirrus paivai new species