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This species has been observed on Reunion and Mayotte Islands

Unassigned Heterobranchia Superfamily : Acteonoidea Family : Bullinidae Distribution : Tropical and subtropical Indo-West Pacific Maximal size : 20 mm Abundance : Seldom : on the rocky coast Species characteristics : White animal with only two black eyes visible on the head between the headshield processes White creamish shell with undulating axial red lines crossed with two (only one in this specimen) other spiral lines
	Showing species characteristics...	Photo Hugues Flodrops Réunion, Etang salé les bains rocky coast, less 1m, 29 November 2007, size : 15 mm

See more about : Sightening and mating periods

Remarks :

Identification confirmed by Bill Rudman
    Synonymous : (according Worms)
          - Bulla lineata Gray, 1825                                      - Voluta ziczac Megerle von Mühlfeld, 1818
          - Voluta scabra Gmelin, 1791                           

Bibliographic data :

Bullina lineata retains a thin operculum and is able to retract completely back into its shell.
    It is found intertidally and in the shallow intertidal through most of its range but at the temperate extremes it is usually found subtidally (Japan, New Zealand).
    Rudman (1971, 1972) suggested that the similarity of its foregut anatomy to that of Hydatina made it reasonable to assume that Bullina eats polychaete worms. Taylor (1986) reported the remains of sedentary cirriform polychaetes in the gut, which suggests that like Hydatina, they feed on cirratulid polychaetes
      

References :

Bill Rudman Seaslug site : Sea Slug Forum : Bullina lineata
   Nudipixel Bullina lineata

Publications :

Gray, J.E., (1825). A list and description of some species of Shells not taken notice of by Lamarck. Annals of Philosophy, or Magazine of Chemistry, Mineralogy, mechanics, and the Arts; by T.Thomson. New Series (Ed. R.Phillips), 9 : 134-140, 407-415.
    Rudman, W.B. (1971) The genus Bullina (Opisthobranchia, Gastropoda) in New Zealand. J. Mal. Soc. Aust. 2(2) : 195-203
    Rudman, W.B. (1972) Studies on the primitive opisthobranch genera Bullina Ferussac and Micromelo Pilsbry. Zoological Journal of the Linnean Society, 51(2) : 105-19, 8 figs
    Taylor, J.D. (1986) Diets of sand living predatory gastropods at Piti Bay, Guam. Asian Marine Biology, 3 : 47-58

Other photos of Bullina lineata :

Hugues Flodrops   Réunion, Etang salé les bains on the rocky coast, 2 m, 6 December 2007, Size : 18 mm Specimen with a more classical pattern : two red spiral line

Hugues Flodrops   Réunion, Etang salé les bains on the rocky coast, 2 m, 18 December 2007during the night, Size : 15-20 mm The white spawn of this species similar to Micromelon undata spawn. Specimen with a more classical pattern : two red spiral line

Christophe Cadet Réunion, Etang salé les bains on the rocky coast, 1 m, 13 September 2009, Size : 12 mm The black spots visible on the head, are the two eyes

Florence Trentin   Réunion, 1 November 2016

Remy Eudeline Mayotte, Sakouli lagoon, less 1 m, 16 November 2017

Reunion, Bullina lineata spawning event, at Etang salé, by Christophe Cadet