Complex sentence: It is an extremely distinctive fungus which comprises a wavy-edged, saucer-shaped disc, whose upper surface is bright orange and smooth while the lower surface is greyish orange and rather powdery.
Split into simpler sentences: It is an extremely distinctive fungus which comprises a wavy-edge, saucer-shaped disc. Upper surface is bright orange and smooth while the lower surface is greyish orange and rather powdery.