Limacodidae, also known as slug moths, comprise about 1,000 species worldwide (Epstein et al., 1998). This moth group is characterized by two adult characteristics: the presence of the female legs with the recessed pad of sensilla trichodea underneath and the entire, disk-shaped papillae anales, and four characteristics in immature stages: the absence of the crochets in all instars of larvae; the presence of the extended pupal maxilla, contiguous with the labial palpus; the hard, ovoid cocoons, lid invisible when uneclosed; and the flat, thin eggs (Epstein, 1996). Since Fixsen (1887), a total of 19 genera and 26 species of Limacodidae have been recorded from Korea. In the present paper, we reported three species of Limacodidae new to the Korean fauna: Ceratonema butleri Kawada, 1930, Microleon decolatus Sasaki, 2016, and Isopenthocrates japona Yoshimoto, 2004.

The family Limacodidae, which is generally known with a Korean common name, ‘Sswaegi’, belongs to the superfamily Zygaenoidea. Most species have strong hair-like bristles, which causes painful skin irritation on outer surface of larval stages. Members of the family are small to medium sized moths and can be defined with the combination of the following characteristics: larvae without crochets, adults with R3, R4 and R5 veins of the forewing stalked and papillae anales disk-shaped. The family contains approximately 1,000 species of 400 genera from the world and a number of species recorded from the tropical regions. In Korea, seven species were studied by Fixen (1887) for the first time. Since then, some fragmentary reports and taxonomic studies were made by several lepidopterists. Although there are 25 species of 19 genera known from Korea, comprehensive study for Korean limacodids has not carried out up to date. As the preliminary step for a revisional study on Korean species of the family, a literature review has been done, and some corrections were made on incorrect scientific names in ‘Checklist of Korean insects (2010)’, which was most recently published.