Meeting Abstract
Aphroditiformia is a clade of annelids with over 1000 described species. Most scaleworms are free living, however many within Polynoidae are commensals with other animals. One genus, Branchipolynoe, currently contains three named species that are only found living commensally in mussels from hydrothermal vents and methane seeps. Three new species of Branchipolynoe were recently discovered from Pacific Costa Rican methane seeps. These newly discovered species live in three different species of Bathymodiolus mussels (also new) at depths from 1000 m to 1800 m. Two of the new Branchipolynoe species show specificity with single host mussel species. The third species occurs in two mussel species. Maximum likelihood phylogenetic analyses were performed on separate and concatenated CO1 and 16S data sets rooted with Branchinotogluma, a closely related genus of scaleworms. One new Branchipolynoe species is most closely related with B. symmytilida, the only named Branchipolynoe species from the East Pacific, while the other two species form a clade that is sister group to Branchipolynoe from the other side of the Panama Isthmus.
