Early Life History of Fish ( and ) in the Nakdong River Water System.

The purpose of this study is to investigate the early life history of the fish, and , in the Nakdong River to use as the preliminary data for the systematic study. The embryos used in the study were fertilized eggs (embryo) and larvae after artificial fertilization. The long diameter of the eggs of the was 3.39-3.97 mm (average 3.68±0.41 mm, n=30) and the short diameter was 1.36-1.55 mm (average 1.45±0.13 mm, n=30). The long diameter of the eggs of the was 2.53-2.71 mm (average 2.62±0.12 mm, n=30) and the short diameter was 1.47-1.60 mm (average 1.53±0.09 mm, n=30). Hatching time was 48 hours for the and 50 hours for the given that the average water temperature was 21.5°C. The hatched larvae were 4.95-5.00 mm (average 4.98±0.04 mm, n=5) for the and the total length was 3.66-3.69 mm (average 3.67±0.02 mm, n=5) for the . was found to be 15.5-15.8 mm at total length (average 15.6±0.21 mm, n=5) on the 56 days after hatching with the number of dorsal fins being iii-9, anal fins iii-10, ventral fins iii-5. The was found to be 15.8-16.0 mm (average 15.9±0.14 mm, n=5) at total length on the 58 days with the number of dorsal fins being iii-11, anal fins iii-12 and ventral fins iii-5 where the number of all fin stalks reached maximum.