|The live animal of Micromelo undatus, head end towards the right|
informal group Lower Heterobranchia
This species occurs in the Caribbean, Florida, Costa Rica, Panama, Bermuda, Brazil, Cape Verde Islands, Canary Islands, Ascension Island, Eastern Atlantic, South Africa, Japan, Thailand and the State of Hawaii.
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.
This species lives in shallow water, up to 5 m in depth, on soft substrates and on the algal turf areas of rocky reefs.
This snail feeds on cirratulinid polychaete worms. The toxins from these worms become incorporated into the snail's tissues and are then used for the bubble snail's own defense.
- "Conquiliologistas do Brasil". Retrieved 2009-10-04.