What is the source of the vertical mesh (ring) in this figure and how does one eliminate it?
SphericalPlot3D[
Abs[.5 + Sin[2 ϕ]/2] Sin[θ] +
Abs[.5 + Sin[2 (ϕ + π/2)]/2] Sin[θ],
{θ, 0, π}, {ϕ, 0, 2 π},
PlotStyle -> {Opacity[0.3], Yellow},
BoxRatios -> {1, 1, 1/2},
MeshFunctions -> {#3 &},
Mesh -> 5,
MeshStyle -> Blue]