New Data to the Earthworm Fauna of the Korean Peninsula with Redescription of Eisenia koreana (Zicsi) and Remarks on the Eisenia nordenskioldi Species Group (Oligochaeta, Lumbricidae)

Yong Hong and Csaba Csuzdi (2016) The earthworm fauna of the Korean peninsula, especially the Northern part (Democratic People's Republic of Korea) is still poorly known. Altogether 148 earthworm taxa are reported from Korea of which 22, including some uncertain records, belong to the Holarctic family Lumbricidae. From these 22 lumbricid taxa only eight are thought to be autochthonous, including the widely distributed Eisenia nordenskioldi species group which consists of six highly diverged DNA lineages. Due to a lack of material, the phylogenetic affinities of the Korean E. nordenskioldi s.l. specimens have not been determined so far. Here we report on the first lumbricid records from the Northern part of the peninsula (DPRK) after the description of the endemic earthworm species Eisenia koreana (Zicsi, 1972) together with a redescription of its type specimens. The supposedly autochthonous Eisenia nordenskioldi species group is briefly reviewed and the specimens collected recently in South Korea (Republic of Korea) were DNA barcoded and compared to the published lineages from Siberia (Russia). The redescription of the type specimen of Eiseniella koreana confirmed its inclusion in the genus Eisenia. Barcoding of the unpigmented Korean E. nordenskioldi specimens revealed that they form an independent clade placed quite far from the previously published unpigmented E. nordenskioldi forms and might represent a distinct species.