A new species of the genus Onychiurus is described from Korea(Jeoksang Mountain in Muju). The genus Onychiurus was elected by Gervais in 1841 with type species Podura ambulans Linneus, 1758. 49 specis of Onychiurus have been reported worldwide, of which only one species, O. polychaetosus, have been recorded from Korea. This genus is characterized by postantennal organ with compound vesicles, antennal Ⅲ sense organ with 2 sensory clubs, furca reduced to a small area of fine ganulation with 2+2 posterior setulae arranged in a row, seta d0 on a head and anal spines present. Onychiurus sp.1 is characterized by the peculiar distribution of dorsal (32/0,2-3,2-3/33333) and ventral (1/000/0101) pseudocelli that allow to distinguish it from the other congeneric species. Antennal segment Ⅲ with four guard setae, two sensory rods, two bent and granulated sensory clubs and five papillae irregular in shape. Postantennal organ consists of 10-12 finely granulated vesicles and tibiotarsi with distal whorl composed of nine setae.

The genus Xenylla Tullberg in the family Hypogastruridae is cosmopolitan, containing about 131 species at present in the world. However, the genus Xenylla of Asia has been very poorly investigated; in Japan, four species, X. acauda Gisin, X. arenosa Uchida & Tamura, X. brevispina Kinoshita, and X. longicauda Folsom, were recorded, only three species, X. boerneri Axelson, X. changlingensis Wu and Yin, and X. changchunensis Wu and Yin, was known to occur in China. In Korea, the first recognizable species of the genus Xenylla was only one listed by Lee in 1973: Xenylla brevispina Kinoshita, 1916. Later Park et al (2005) added four new species, X. convexopyga, X. dotata, X. longistriata, and X. marina, which collected from litter of coniferous and broad-leaved trees, soil layer of a deciduous forest and dry accumulated organic matter on the margins of saline water. One new species of the genus Xenylla that were found from Korea is found. The new species characterized by labral setae arrangement and tiny anal spines. The present species resembles X. dotata in the arrangement of dorsal and ventral setae. But it is easily distinguished from X. dotata by the length ratio of furca, morphology of mandible, the shape of dorsal setae upon fourth antennal segment, and the length of anal spine. As result of this study, Korean faunal list of Xenylla adds up to 6 species.