A new Capitella polychaete worm (Annelida: Capitellidae) living inside whale bones in the abyssal South Atlantic

- A new Capitella species has been described for deep sea whale falls communities.
- The new species is one of the most abundant polychaetes inhabiting the bones.
- High genetic divergence between the new species and the other ones.
- Occurrence of hermaphroditism due to the opportunistic life history of the group.
- Population dynamics controlled by organic matter and high concentration of sulfide.

A new species of the genus Capitella, Capitella iatapiuna sp. nov., has been found in deep sea whale-fall samples, São Paulo Ridge-Southwest Atlantic. The new species is mainly characterized by a bluntly rounded prostomium and a very distinct peristomium forming a complete ring. Ribosomal 16S sequences were obtained and used for inter-specific comparisons. This species is herein described and compared to others species of the genus. Its ecological role in the whale-fall community is also discussed.