UC San Diego

Dorvilleidae is a well-represented group of annelids that are commonly associated with chemosynthetic habitats. Currently, there are 11 described Parougia species, of which two are found at vents or seeps: Parougia wolfi and Parougia oregonensis. Eight new Parougia species are recognized and described in this study from collections in the Pacific Ocean, all from >586 m depth at whale-falls, hydrothermal vents, and/or methane seeps. The specimens were studied using morphology and phylogenetic analyses of DNA sequences from mitochondrial (cytochrome c oxidase subunit I, 16S rRNA, and cytochrome b) and nuclear genes (18S rRNA and Histone 3). We found six sympatric Parougia spp., from Hydrate Ridge, Oregon and four Parougia spp. capable of inhabiting different types of chemosynthetic habitats. Two new species had a most remarkable distributional range and depth, from Oregon to Costa Rica seeps (>5500 km; 587-1583m). The dorvilleid genus Ophryotrocha has previously been highlighted as diversifying in the deep-sea environment. Our results emphasize the hitherto unknown diversity of other taxa such as Parougia at these chemosynthetic systems.