mesopterygium

例句：

1. 1. The mesopterygium is a rare and beautiful bird.
   这个鸟类稀有且美丽。
2. 2. The mesopterygium is known for its unique wing shape.
   这个鸟类以其独特的翅膀形状而闻名。
3. 3. The mesopterygium is a protected species in many countries.
   这个鸟类在许多国家都是受保护的物种。