Key to species of Sigambra found in Brazilian waters

1. Notopodial hooks from the third or fourth chaetiger.......................................................... 2

- Notopodial hooks from chaetigers 9–29.................................................................... 3

2. Notochaetae include hooks and simple chaetae, hooks from third or fourth chaetiger, neurochaetae capillary slender slightly serrate..................................................................... Sigambra setosa Fauchald, 1972

- Notochaetae include hooks only, hooks from fourth chaetiger, tentacular segment with anterior margin with rounded projected lobes, external to lateral antennae........................ Sigambra sp. indet. (recorded by Salazar-Vallejo et al., 2019)

3. Notopodial hooks from chaetiger 11–15, capillaries smooth and serrated, either straight or slightly curved, sometimes emergent....................................................................... Sigambra bassi (Hartman, 1945)

- Notopodial hooks from chaetigers 9–29, capillaries hirsute, thin and ventrally curved........ Sigambra grubii Müller, 1858