Koegelenberg stays with Zebre
Koegelenberg, 22, arrived in Italy in the middle of the 2014/2015 season after representing Boland, Sharks and the Lions during his youth career.
"I am very happy to stay at a club that has given me confidence and the opportunity to play at the highest level of professional rugby," said Koegelenberg.
"That is why I decided to continue to wear this shirt."