The Niger–Congo languages, one of the largest language families in the world, are predominantly spoken in the southern and central regions of Nigeria. Key languages within this family include Yoruba, Igbo, and Fulfulde, among others.

1. Yoruba: Primarily spoken in the southwestern region of Nigeria, the Yoruba language is one of the most widely spoken languages in the country, with millions of speakers.

2. Igbo: This language is predominantly spoken in the southeastern part of Nigeria. Like Yoruba, Igbo has a significant number of speakers and is an important cultural language in the region.

3. Other Languages: Other Niger–Congo languages spoken in Nigeria include various dialects and languages such as Edo, Efik, Ibibio, and many others, primarily found in the southern parts of the country.

The distribution of these languages reflects Nigeria's diverse ethnic composition, with over 250 ethnic groups and their respective languages. If you're interested in more specific details about a particular language or region, please let me know!