Palaeolake Mega-Chad or Mega Chad (largest fresh water lake ever known to exist in the world)

 https://www.iflscience.com/environment/sahara-recently-hosted-worlds-largest-freshwater-lake/

https://insider.si.edu/2010/12/ancient-megalake-discovered-beneath-sahara-desert/

https://www.thevintagenews.com/2016/09/19/huge-lake-middle-sahara-desert-named-mega-chad/

While it has no entry, it can be found mentioned here

https://en.wikipedia.org/wiki/Lake_Chad#History

And ironically here

https://en.wikipedia.org/wiki/African_humid_period

Interesting blog about creating it again

Study shows Lake Mega-Chad dried up far more quickly than thought

https://phys.org/news/2015-06-lake-mega-chad-dried-quickly-thought.html