A dwarf Japanese Maple with a round form. 'Koto maru' originated as a witches broom mutation. The center lobe on the leaf is shorter and rounded, which gives the leaves a very interesting appearance. The spring color is green with an orange blush and red edging on the margins. The summer color is green with rose highlights. As the tree matures, the leaves reduce in size. The fall color is orange-yellow. The name means "rounded harp". A fantastic selection for container gardening or to fill a small space in the garden.