Spionid polychaetes are dominant members of many marine soft-bottom communities. As such, understanding their diversity and evolutionary history is of general interest. One spionid group in particular,
Laonice, is known from the North Atlantic with several species occurring in deeper waters. We explored, as part of the IceAGE project, the biodiversity and evolution of
Laonice using both morphology and mitochondrial cytochrome c oxidase subunit I (COI) gene data. Our data confirm the existence of at least seven lineages of
Laonice in waters surrounding Iceland. Additionally, our sampling suggests species distributions of
Laonice are similar to previous reports for other annelids, in that warmer waters south of Iceland appear to harbor more species, but further work is needed to clarify distribution patterns. Although our analysis was hampered by quality of preservation of animals from deep water, we recovered several species that were previously known to science (e.g.,
Laonice blakei,
Laonice sarsi,
Laonice cf.
norgensis, and
Laonice cirrata) and one new species.
Laonice plumisetosa sp. nov. is characterized by having u-shaped nuchal organs not exceeding chaetiger 1 and the presence of stout capillaries with plush-like texture in parapodia of anterior chaetigers. Uncorrected genetic distances and phylogenetic analyses of COI data confirm these
Laonice lineages are distinct. However,
L. cirrata is composed of three subclades suggesting unrecognized diversity within this species. In the present paper, we aim to provide a preliminary phylogeny for
Laonice and discuss our results in relation to the recently proposed subgenera for
Laonice.