  We present a new analysis of the anisotropic spectral energy distribution in
incompressible magnetohydrodynamic (MHD) turbulence permeated by a strong mean
magnetic field. The turbulent flow is generated by high-resolution
pseudo-spectral direct numerical simulations with large-scale isotropic
forcing. Examining the radial energy distribution for various angles $\theta$
with respect to $\mathbf{B}_0$ reveals a specific structure which remains
hidden when not taking axial symmetry with respect to $B_0$ into account. For
each direction, starting at the forced large-scales, the spectrum first
exhibits an amplitude drop around a wavenumber $k_0$ which marks the start of a
scaling range and goes on up to a dissipative wavenumber $k_d(\theta)$. The 3D
spectrum for $k \ge k_0$ is described by a single $\theta$-independent
functional form $F(k/k_d)$, the scaling law being the same in every direction.
The previous properties still hold when increasing the mean field from $B_0=5$
up to $B_0=10 \ b_{rms}$, as well as when passing from resistive to ideal
flows. We conjecture that at fixed $B_0$ the direction-independent scaling
regime is reached when increasing the Reynolds number above a threshold which
raises with increasing $B_0$. Below that threshold critically balanced
turbulence is expected.
