First Report of a Paucibranchia (Polychaeta, Eunicidae) Species without Lateral Palps in Korean Subtidal Waters, with Genetic Evidence for Its Taxonomic Position

An undescribed species belonging to the family Eunicidae was detected in a sublittoral habitat of southern coast Korea. This Korean eunicid initially thought belong genus Lysidice based on its general appearance, including absence prostomial lateral palps and peristomial cirri. However, more detailed characterization morphological features maxillae mandible coupled with mtCOI 18S rRNA gene sequence analyses confirmed that this is member Paucibranchia. The found intact adult specimens 153 segments unique feature not previously reported Thus, new species, Paucibranchia triantennata sp. nov., can be easily distinguished from other known congeneric species. Except for palps, P. nov. resembled conferta, gathofi, patriciae shape prostomium, brief location branchiae, compound spinigers. could clearly these by shorter antennae, large number subacicular hooks, falcigers.