Taxonomy And Geographical Distribution Of Eunicidae And Onuphidae (polychaeta: Eunicida) From China Seas

Eunicidae and Onuphidae are two common polychaete groups with high speciesdiversity and abundance, worldwide distribution, and diverse habitats and lifestyles,receiving much attention in the taxonomical study. However, little study had beendone on Chinese eunicids and onuphids and our knowledge about their taxonomy andgeographical distribution is insufficient. Based on the historical materials deposited inthe Marine Biological Museum of Chinese Academy of Sciences, including recentlycollected specimens from offshore areas and coastal regions of Hainan Island, wecarried out a systematic study on both two families. A total of32species of Eunicidaebelonging to6genera are identified, including3newly discovered species and10newly recorded species;21species of Onuphidae belonging to8genera are identified,including9newly recorded species. In the present study, we consult a large number ofliteratures and summarize the research background for each taxon. Morphologicaldescriptions and illustrations including identification key to each genus and speciesare provided; information about their geographical distribution and habitats are listed.We also compare morphologically similar genera and species, discuss some existingproblems in the taxonomical study, and clean up the synonyms of some involvedspecies.The taxonomical study shows:1) the frequently recorded species in the Chineseintertidal zone, Diopatra chiliensis Quatrefages,1865, is actually Diopatra sugokaiIzuka,1907;2) the dominant species in the Yellow Sea which was identified asOnuphis geophiliformis (Moore,1903), largely belong to O. tetradentata Imajima,1986.The study of the geographical distribution shows:1) only3species of Eunicidaeare distributed in the Bohai and Yellow Seas,17species in the East China Sea,30species in the South China Sea, in which15species inhabit coral reefs in Hong Kong, Hainan Island, Xisha Islands and Nansha Islands at depths of2–12m. A total of14species are restrictedly distributed in the South China Sea and belong to typical warmwater species, while the others spread to the East China Sea and a few species evenadapt to the temperate environment in the Yellow Sea.2)4species of Onuphidae aredistributed in the Bohai Sea,8species in the Yellow Sea,11species in the East ChinaSea,13species in the South China Sea. The Chinese onuphids have a complicateddistribution pattern. Some species are restricted to the South China Sea and representtypical warm water species, while some others are restricted to the Bohai and YellowSeas and belong to cold water species of north temperate waters.The present study not only enriches the knowledge about Chinese marinebiodiversity, but also provides basic data for subsequent research of phylogeny,marine ecology, biological resource protection and ocean environmental evaluation.