Key for the species of Pectinariidae reported from off the Brazilian coast

1. Opercular margin smooth................................................................................ 2

- Opercular margin with cirri.............................................. Amphictene catharinensis (Grube, 1870)

2. Cephalic veil with cirri; clearly marked transition between scaphe and posterior body................................ 3

- Cephalic veil smooth, except for medial extension; poorly marked transition between scaphe and posterior body................................................................................................ Petta alissoni n. sp.

3. Numerous pairs of scaphal hooks, from ~10 to more than 20................................................... 4

- Few pairs of scaphal hooks, less than 5..................................................... Pectinaria regalis *

4. Scaphal hooks distally flattened, lanceolate.................................................. Pectinaria gouldii *

- Scaphal hooks distally pointed, slightly curved, sigmoid.................................... Pectinaria nonatoi n. sp.