Three places were available at the South African Open hosted by the City of Johannesburg for the top three players in the top ten not already exempt, and Langasque fired a closing 66 to finish in solo second behind 2010 Claret Jug winner Louis Oosthuizen.
Schwartzel and Wilson finished two shots further back in a tie for third alongside Thomas Aiken and Bryce Easton, claiming the other two places by virtue of their higher positions in the Official World Golf Ranking.
For 2011 Masters Tournament winner Schwartzel, it will be a 15th Open appearance and 11th in a row as he goes in search of a second Major Championship.
“It’s a nice bonus,” he said. “I was hoping to do better in this tournament but I’m still happy that I get to play The Open in Northern Ireland which will be really nice.
“Watching Ernie’s last win and when Tiger won at Hoylake are two of my best memories of The Open and obviously when my good friend Louis won at St Andrews.
“It’s special. There’s so much history behind it and it would be nice to have my name on the trophy one day.”
Langasque finished in a tie for 65th at the 2015 Open after earning his place in the field by winning The Amateur Championship at Carnoustie Golf Links the previous month.
“It’s amazing,” he said. “All week long I was focused on making it a good week and I didn’t think about the place for The Open. But I played really nicely today and the conditions were really tough, but I just stayed focused and now I’ve qualified. I’m really happy.
“I think Portrush will be a totally different course. It was good to play in St Andrews for my first Open because it's quite wide and I could play left if I couldn’t quite feel the shot.
“Portrush is not quite the same, the course is more narrow but I think I’m ready to play these kind of events as a pro. I’m going to be patient and not put too much pressure on myself and do my best and enjoy myself over there.
“I’m ready. My game is ready. My last results have been good. Golf can go quick in every sense. I will continue to work and focus on the tournaments coming up and then on The Open and we will see what will happen.
“Everything has gone really quick - three months ago I was on the Challenge Tour and I didn't have a card and now I've qualified for The Open so I'm really really happy.
“I'll just continue on the way I am and some good things are coming, I think.”
Wilson appeared in four consecutive Opens from 2007 and returned to the oldest Major last season - with a tie for 24th in 2009 his only made cut.
“I’m delighted,” he said. “It wasn’t really something I was thinking about going out there today. I was pleased to sneak in and get this spot because I bogeyed the last hole and I thought it was going to cost me the spot.
“This is quite big to know that you’re in The Open at this stage of the year. It’s great that I can have something that I’m really looking forward to. I managed to get in last year and it’s where you want to be. You never want to miss The Open.
“The Open is the best one there is. I played it this last year but I hadn’t played it for a few years.
"Coming back and seeing what is was like at Carnoustie, the infrastructure there and knowing the eyes of the whole world are on the tournament. You want to be there, everything about it and the way that it was run was fantastic. To qualify and get in there is nice.”