diff --git a/skimage/exposure/unwrap2D.pyx b/skimage/exposure/_unwrap_2d.pyx
similarity index 100%
rename from skimage/exposure/unwrap2D.pyx
rename to skimage/exposure/_unwrap_2d.pyx
diff --git a/skimage/exposure/unwrap3D.pyx b/skimage/exposure/_unwrap_3d.pyx
similarity index 100%
rename from skimage/exposure/unwrap3D.pyx
rename to skimage/exposure/_unwrap_3d.pyx