Micromelo undatus, common name the miniature melo, is an uncommon species of small sea snail or bubble snail, amarine opisthobranch gastropod mollusk in the family Aplustridae.
This species lives in shallow water, up to 5 m in depth, on soft substrates and on the algal turf areas of rocky reefs.
The thinly calcified shell is covered with undulating brown lines, crossed with two other spiral lines. The shell length is 12 to 17 mm.
The large, colorful body is blue with white spots. The margin of the foot has a diffuse blue line. source