Abstract
Zhi Wang, Yanjie Zhang, and Jian-Wen Qiu (2018) Marphysa hongkongensa n. sp. (Annelida: Eunicidae) is described based on samples from the intertidal zone of Tolo Harbour, Hong Kong. This new species belongs to the Marphysa sanguinea species complex. It is characterized by a subacicular hook from chaetiger 26-58 to the posterior end, branchiae with up to 5-10 filaments from chaetiger 14-35 to the posterior end, and four types of pectinate chaetae. Molecular analyses indicated that the cytochrome oxidase c subunit I gene and 16S RNA gene of Marphysa hongkongensa diverged from the corresponding sequence of the closest related species of Marphysa in GenBank by 19.5% and 12.1%, respectively. An identification key is provided for species in the Marphysa sanguinea complex along the Chinese coast.