*Tyrone Davis and Na Onka Mixon are among the group of 20 castaways set for CBS’ upcoming “Survivor: Nicaragua.”

The cast of season 21, finally revealed this morning, will be split along age lines. Youngins 30 and under comprise the LaFlor (yellow) tribe, while the Espada tribe (blue) is for the over 40 crowd.

Tyrone, a 42-year-old fire captain from Inglewood, Calif, joins a team that includes former NFL coach and current TV analyst Jimmy Johnson.

The former elementary school teacher says in his past, “I’ve been shot at, I’ve been in altercations, I’ve been approached to sell drugs. I know several people in the element, put it like that. And I got tired of seeing some of my childhood buddies buried.”

Na Onka Mixon

Na Onka, 27, is a PE teacher and also from Los Angeles. She fancies herself a “chameleon” who can “adapt to anything,” according to her video on the “Survivor” website.

“If I need to be jolly, I’ll be jolly. If I need to be hood, I’ll be hood. If I need to be valley, I’ll be valley,” she says. “I’m the lethal weapon, I’m the secret weapon that they don’t even know about. My tribe isn’t even gonna know.”

“Survivor: Nicaragua” premieres Sept. 15 at 8 p.m.