Journal of the Marine Biological Association of the UK

Research Article

Kirkia heterobranchiata, a new genus and species of extratubular brooding sabellid (Polychaeta: Sabellidae) from São Paulo, Brazil

João M.  de M. Nogueira a1, Eduardo  López a2 and Maíra C.S.  Rossi a1
a1 Departamento de Zoologia, Instituto de Biociências, Universidade de São Paulo (IB–USP), Rua do Matão, travessa 14, n. 101, 05508-900, São Paulo, SP, Brazil, e-mail:
a2 Departamento de Biología, Unidad de Zoología, Universidad Autónoma de Madrid, Cantoblanco, 28049, Madrid, Spain, e-mail:

Article author query
de m nogueira jm   [PubMed][Google Scholar] 
lopez e   [PubMed][Google Scholar] 
rossi mc   [PubMed][Google Scholar] 


A new genus and species of sabellid polychaete from an organically enriched beach in São Sebastião, State of São Paulo, is described. Kirkia heterobranchiata is unique among sabellids for brooding the embryos on the dorsalmost pair of radioles, which exhibits several modifications for this purpose, rather than on ventral radioles. Morphologically, K. heterobranchiata is most closely related to Perkinsiana riwo, here referred to as the new genus, as suggested by phylogenetic analysis. The new genus is characterized by the shape of the lips (dorsal lips roughly triangular, broader than long; ventral lips lower, ventrally fused and distally rounded), by the absence of both radiolar and pinnular appendages, by having uncini with very short handles in both the thorax and abdomen, and by the ability to brood embryos in cocoons attached to the branchial crown.

(Received February 4 2003)
(Accepted May 24 2004)