New record of family of arhynchobdellida leeches (Orobdellidae) from Gageodo Island is presented. We have surveyed for land leeches in Korea from July to September in 2011 and found 1 species. This is Orobdella tsushimensis Nakano, 2011, reported for the first time in Korean Peninsula. This species gets the following characteristics: IV unianulate; 1/2+5 annuli between gonopores; bottle-shaped gastroporal duct; and epididymides in XVII–XIX. According to their morphological features, the diagnosis of O. tsushimensis is slightly emended. Phylogenetic analyses using mitochondrial COI, tRNACys, tRNAMet, 12SrDNA, tRNAVal and 16SrDNA markers show that the Orobdella specimen from Gageodo Isl. and O. tsushimensis from Tsushima Island, Japan, form a monophyletic clade and also confirm the identification of the Orobdella specimens from Gageodo Isl.

New record of family of arhynchobdellid leeches (Hirudiniformes: Haemadipsidae) from Korea is presented. We have surveyed for land leeches in Korea from July to September in 2011 and found 1 species. This is Haemadipsa rjukjuana Oka, 1910, reported for the first time in Korean Peninsula. This species is terrestrial blood-feeding leech which attacks medium or large sized mammals primarily, including human and originally distributed in East and South East Asia, including Indochinese Peninsula, Malay Peninsula, Ryukyu Islands and Taiwan. In Japan, the number and areas of habitats of land leech have been rapidly expanded since 1970s and many leeches attack forest workers, hikers and resident during May to September. As a result of climate change, same situation can be reproduced in Korean Peninsula. We firstly report the occurrence of blood-feeding land leech, the behavior on human being and distributions in Korea. Also, we obtained the sequence of the mitochondrial gene (COI) and additional biology is discussed for this species according to collection data.