nigricans

例句：

1. 1.The nigricans are the most common race in Africa.
   暗色人种是非洲最常见的种族。
2. 2. The nigricans have a rich cultural heritage.
   暗色人种拥有丰富的文化遗产。
3. 3. The nigricans have been facing discrimination due to their skin color.
   由于肤色，暗色人种一直面临着歧视。