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This species has been observed on Reunion and Mayotte Islands

Order : Cephalaspidea Superfamily :  Haminoeidea Family : Haminoeidae Distribution : Indo-West Pacific Maximal size : 20 mm Abundance : Species characteristics : It is green to brownish, sometimes with brown or white patches Body stout with a brownish to green, well calcified external shell On each side the foot extends into a large lateral lobe, the parapodia, which fold over, partially enclosing the shell, which lies exposed on the back of the animal.
	Showing species characteristics...	Photo Christophe Cadet Réunion, Etang salé on the rocky coast, less 1 m, 2009

See more about : Sightening and mating periods

Remarks :

Identification confirmed by Nathalie Yonow
    Synonymous (according worms):
              - Bulla calyculata Broderip & G. B. Sowerby I, 1829 (original combination)         - Bulla viridis Rang in Quoy and Gaimard, 1832
              - Bulla glauca A. Adams, 1850                                                                     - Glauconella adamsi Gray, 1850
              - Bulla minor A. Adams, 1850                                                                       - Linteria acuminata G. B. Sowerby II, 1870
              - Bulla smaragdina A. Adams, 1874                                                             - Smaragdinella viridis (Rang in Quoy and Gaimard, 1832)

Bibliographic data :

Brownish to green shell ear-shaped, very short spiral, a prominent spoon shaped callus top of the columella. There is some variability in shell form
    The large headshield is relatively wide in front, narrowing slightly to form a rounded bilobed posterior end
    The chemosensory Hancock's organs are brown and form a thin wrinkled ridge in the groove between the foot and the headshield on each side of the head.
    Miller (1969) noted that in the Solomon Islands this species attached firmly to open, exposed rock surfaces, and produced large amounts of mucus, sometimes becoming very difficult to prise off. It was found uncovered at low water and was kept moist by the ocean spray.

References :

Bill Rudman Seaslug site : Sea Slug Forum : Smaragdinella calyculata
   Nudipixel Smaragdinella calyculata

Publications :

Miller, M. C. 1969. The habits and habitats of the opisthobranch molluscs of the British Solomon Islands, pp. 541-548. [In]: E. J. H. Corner. A discussion of the results of the Royal Society Expedition to the British Solomon Islands Protectorate, 1965. Philosophical Transactions of the Royal Society London, series B, Biological Science, 255(800) : 285-631.
    Rudman, W.B. (1972) The herbivorous opisthobranch genera Phanerophthalmus A. Adams and Smaragdinella A . Adams. Proceedings of the malacological Society of London, 40(3) : 189-210, 11 figs

Other photos of Smaragdinella calyculata :

Frédéric Ducarme Mayotte, Mtsanga Fanou, May 2018

Maurice Jay Réunion, Shell ref : 602 Collection Maurice Jay Brownish to green shell ear-shaped, very short spiral, a prominent spoon shaped callus top of the columella.     Living on the basaltic rocks in the tidal zone . Rare.     Maximal shell size : 8,2 mm.

Nathalie Rodrigues Réunion, Terre sainte, less 1 m, 19 February 2016     A brownish specimen

Nathalie Rodrigues Réunion, Terre sainte, less 1 m, 14 February 2016, size : 10 mm During the night With a green algae growing on the shell (a) ...

Christophe Cadet Réunion, Etang salé on the rocky coast, less 1 m, 28 December 2010, size : 12 mm

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