TURTLE ANT Soldier
The bizarre disc on the head is used as a living door to block the nest entrance. To enter the nest in a mangrove twig, a foraging worker must pass this door-guarding soldier whose head is roughly the same size and shape as the entrance. These ants don’t build the nests themselves; rather, they inhabit burrows made by beetle larvae.
Turtle ants aren’t fighters. Rather, they’re all about defense. If a colony gets hold of an old beetle burrow, the heavily armored majors will plug the entrance with their head shield and sit tight, budging only to let their nestmates pass. They are literally living doors.
Fact Source and more photos:
Other photos you may like:
Ant in the setting sun
Crab Spider looking like an ant
Leaf Cutter Ants doing their thing