How do folding wings maintain structural integrity? Removable wings?

[WK95]

Without a single full lengthed spar going through the whole length, how do folding wings and removable wings be designed such that they maintain structural integrity in flight and other motions involving declarations and accelerations?

For example, this is the folding wing of a Sonex Onex aircraft. I'm sure it's safe but how come it is?

What is that mechanism I see to the left of the hinge? Is that something for locking the wing in position?

 

[phinds]

that mechanism to the left of the hinge appears to be a multi-point locking mechanism and you'll note that there is a full plate on both sides of the joint, so there won't be an movement of the joint once it's locked in place. That must be enough to do the trick.