  The spectral branching behavior of the 2x2 operator matrix of the
magneto-hydrodynamic alpha^2-dynamo is analyzed numerically. Some qualitative
aspects of level crossings are briefly discussed with the help of a simple toy
model which is based on a Z_2-graded-pseudo-Hermitian 2x2 matrix. The
considered issues comprise: the underlying SU(1,1) symmetry and the Krein space
structure of the system, exceptional points of branching type and diabolic
points, as well as the algebraic and geometric multiplicity of corresponding
degenerate eigenvalues.
