uropatagium

例句：

1. 1. The uropatagium is a rare and valuable species of fish.
   鱼鳔是一种稀有且珍贵的鱼类。
2. 2. The uropatagium plays a crucial role in the growth and development of the embryo.
   鱼鳔在胚胎的生长和发育中起着至关重要的作用。
3. 3. The uropatagium has been used as an indicator of environmental pollution for many years.
   鱼鳔多年来一直被用作环境污染的指标。