These are large with the soldier reaching a body length of 7-13mm and the queen, 25mm.Grass and other plant matter is collected for storage.
Nest system are 1.5 – 7m underground and diffuse, tunnels leading from piles of cut grass and numerous, turreted soil dumps to temporary subterranean grass-storage shelves. All tunnels finally descend to spherical hives (up to 20), each around 60cm in diameter, surrounded by grass-storage chambers and made of fragile, black, horizontal shelves of chewed vegetable matter.
These are filled with nymphs and house the queen and king.
Info: Field Guide to Insects of South Africa