The first record of Catenula confusa Nuttycombe, 1956 (Platyhelminthes: Catenulida: Catenulidae) from Korea

Free­living freshwater Platyhelminthes are usually divided into two groups, macroturbellarians known as planarians (order Tricladida) and microturbellarians. The latter are less than a few millimeters in length, and inhabit on the surface of sediments, stones and aquatic plants in aquatic environments (Kolasa, 1991). Owing to their richness in freshwater ecosystem and sensitivity to environmental changes, microturbellarinas have poten­ tials as indicator species of water quality (Young, 2001). Approximately 400 species of freshwater microturbel­ larians have been reported and about 350 species and 150 species were described from Europe and North Ame­ rica, respectively (Kolasa, 1991). And in the East Asia, thirty­nine species were recorded from Japan (Kawakatsu et al., 1970­2000). In Korea, however, microturbellarian species has never been reported though three planarian species were described (KSSZ, 1997). Here, I report Catenula confusa Nuttycombe, 1956, which is the first record of microturbellarian species from Korea.