The Lined Bubble Shell (Bullina lineata) is a small opisthobranch species that belongs to the family Bullinidae. This species is known to occur in the waters of the tropical and subtropical Indian and western Pacific Oceans. It has been recorded from the waters of Japan, Hawaii, Indonesia, New Zealand, Lord Howe Island and the east coast of Australia. This species can be found in intertidal rockpools and down to depths of at least 20 metres. This species can be recognised by its translucent blue thin operculum and has the ability to retract completely back into its shell if disturbed.
This species lays a spiral white coloured egg mass, feeds on polychaete worms and as closely related to the Rose Bubble Shell (Hydatina physis). The Lined Bubble Shell (Bullina lineata) grows to a maximum length of approximately 2cm.