  The hidden supersymmetry and related tri-supersymmetric structure of the free
particle system, the Dirac delta potential problem and the Aharonov-Bohm effect
(planar, bound state, and tubule models) are explained by a special nonlocal
unitary transformation, which for the usual N=2 supercharges has a nature of
Foldy-Wouthuysen transformation. We show that in general case, the bosonized
supersymmetry of nonlocal, parity even systems emerges in the same
construction, and explain the origin of the unusual N=2 supersymmetry of
electron in three-dimensional parity even magnetic field. The observation
extends to include the hidden superconformal symmetry.
