Scarlets have signed another South African forward, Johan Snyman, who plays for the Eastern Province side.
The 26-year-old has signed a three-year contract and is expected to arrive in Llanelli within a month.
Scarlets head coach Simon Easterby said: "To be competitive at the top end of Europe, we need strength, power and consistency from our pack.
"This is another key signing for us and we're delighted to have secured Joe to join us at Parc y Scarlets."
Snyman, who is 6ft 7in and 18st 12lb, has had experience with Natal Sharks, Golden Lions - where he was part of the 2011 Currie Cup-winning team - and Hawke's Bay in New Zealand.
He has played for South Africa Under-19s and has built a reputation as a superb lineout technician.
"We made a commitment last season to recruit in key areas and with our new signings we are also mindful of the impact they will have on the development of players we have coming up through our system," Easterby added.
"It also adds to the healthy level of competition within our squad which will further drive and motivate performance across the squad. Different experiences and input from players in the southern hemisphere can only have a positive impact and add to the energy here."
Former Ulster coach Alan Solomons recruited Snyman for his EP Kings side, as the Eastern Cape franchise build towards Super Rugby in 2013.
He made 11 appearances for the Sharks Currie Cup and Vodacom Cup sides before a short spell at New Zealand ITM Cup team Hawkes Bay.
Earle, a former team-mate of Snyman, said: "He's a superb player. I've played with him at the Lions, I actually know him quite well.
"When we played together we used to make a good combination so he's also going to be a good competitor for all the second-rows here, especially me.
"South Africans like to give each other a hard time so it's just going to improve the Scarlet pack and it's just going to bring more experience.
"I won't lie to anyone - I really rated him, so I just tell people that I really rate him and that he won't let anyone down."