Tarsus IV

In “Star Trek: The Original Series” it was a colony world of the United Federation of Planets, with a population of roughly 8,000.
In 2246, the crops which the colony relied on were contaminated by a fungus. The people were starving, and Starfleet was not expected for some time.
The Governor, known as Kodos, knew that the stores of food would last only half of the time feeding the full colony, or the full length feeding half.
He chose the later, and executed 4,000 colonists based upon questionable Eugenicist theories.
There are only Nine survivors who were capable of identifying Kodos, including Captain James T. Kirk and Ensign Riley of the USS Enterprise.

“Oh, Tarsus IV won’t be so different from the Mars Colonies.”