Ulstron

例句：

1. 1. The Ulstron is a rare and valuable species of fish.
   乌斯特龙是一种稀有且珍贵的鱼类。
2. 2. The Ulstron has been extinct for over 500 years.
   乌斯特龙已经灭绝了500多年。
3. 3. The Ulstron was discovered by a team of scientists in the Amazon rainforest.
   乌斯特龙是由一支科学家团队在亚马逊雨林中发现的。