Redescription of a giant mud worm Paraleonnates uschakovi Khlebovich and Wu, 1962 (Nereididae: Polychaeta: Annelida) with special reference to its junior synonym of Periserrula leucophryna Paik, 1977

초록

A nereidid polychaete Paraleonnates uschakovi Khlebovich and Wu was described in 1962 as a new genus and a new species, based on the specimens collected from Chinese coasts of Yellow Sea and South China Sea (Khlebovich and Wu, 1962). Later, Periserrula leucophryna Paik was described in 1977 as a new genus and a new species, based on the specimens collected from the Korean coast of the Yellow Sea. Since Paik (1977) did not refer Khlebovich and Wu (1962) in his description, he seems to be not aware of the description of Paraleonnates uschakovi. Description of Periserrula leucophryna is very similar to that of Paraleonnates uschakovi, with the same unique characteristics, i.e., continuous paragnath rows present around the maxillary ring, and digitate papillae present in both dorsal and ventral surfaces of the oral ring. Thus, Khlebovich (1996) synonymized Periserrula leucophryna to Paraleonnates uschakovi. But, he seemed to judge this without the examination of the type of Periserrula leucophryna. There were a few differences between the original descriptions of these two species: Periserrula leucophryna has uniramous prapodia in the first and second parapodia, and both spinigers and falcigers in parapodia (Paik, 1977), whereas Paraleonnates uschakovi has uniramous prapodia in only the first parapodium, and only spinigers in parapodia (Khlebovich and Wu, 1962; Wu et al., 1995). In the present study, we examined paratype specimens of the both species and additional materials newly collected from the Korean coast, and confirmed that they are correctly synonyms as Khlebovich (1996) noted. Ecology, distribution and other biological aspects of this species are discussed: This species is well known as bait for fishing mullet around Han River estuary in Korea, but also as one of the largest polychaetes (maximum body length: about 2 m long). They mainly occur in highly muddy sediments on the middle to upper region of tidal flats in western Korean coasts. Its distribution pa