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This species has been observed on Reunion, Mayotte and Mauritius Islands

Order : Nudibranchia Suborder : Euctenidiacea Superfamily : Polyceroidea Family : Gymnodorididae Distribution : Indo-West Pacific Maximal size : 55 mm Abundance : Seldom if ever on the reef flat zone Species characteristics : The body is translucent white to pale creamly yellow with bright yellow orange to orange longitudinal ridges. The notal brim and foot margins are the same color The gills are arranged in a transverse row across the back in this species. They are translucent white with a orange line up their front axis. The small and lamellate rhinophores have a translucent stalk and lower half of the clavus with the upper half of the clavus orange
	Showing species characteristics...	Photo Armand Daydé Reunion, Etang Salé les bains lagoon, 1 m, 7 October 2009, during the night, size : 40 mm

See more about : Sightening and mating periods

Remarks :

Identification confirmed by Nathalie Yonow
    For some specialist : The gills are arranged in a transverse row across the back in this species like in Analogium amakusanum, which is why they are both presently placed in the genus Analogium rather than Gymnodoris in which the gills are arranged in a circle as in all other dorids.
    For other specialist : The arrangement of the gills is not sufficient grounds for erecting a new genus Analogium for this species, so they called this species Gymnodoris striata. They also considered Gymnodoris amakusana as a synonyme of Gymnodoris striata because the don't found any anatomical reasons to support this proposal.
    G. striata is most similar to G. amakusana, which has golden lines around the mantle margins and one transverse bar of the same colour immediatly in front of the gills
    Synonymous : (according Worms)
               - Analogium striatum (Eliot, 1908)
               - Trevelyana striata Eliot, 1908

Bibliographic data :

The gills are arranged in a transverse row across the back in this species like in Analogium amakusanum, which is why they are both presently placed in the genus Analogium rather than Gymnodoris in which the gills are arranged in a circle as in all other dorids.
    The sides of the body also bear orange ridges
    There is considerable variability in the orange ridges on the body.
    Gills branches are flattened and leaf-like
    It feeds on other opistobranchs it encounters whilst crawling over or burrowing into sand. It seems to prefer the sand-dwelling sacoglossan Plakobranchus ocellatus
    According Johnson and Boucher, this species lays a yellow spawn mass consisting of a coil of one to three, loose whorls that is only lightly attached to the substrate. Yellow ova (190-240 µm diameter) occur individually within capsules (250-265 µm)

 

References :

Bill Rudman Seaslug site : Sea Slug Forum : Gymnodoris striata
   Nudipixel Analogium striatum

Publications :

Hamatani, I. (1995) A new record on Analogium striatum (Eliot, 1908) (Opisthobranchia: Nudibranchia: Gymnodorididae) from southwestern Japan. Venus, (Japanese Journal of Malacology), 54(3) : 179-183.
    Baba, K. (1996) Taxonomical change for Gymnodoris striata of Baba, 1937 (Nudibranchia: Gymnodorididae) from Amakusana, with a re-description based on some additional specimens from Toyama Bay, Japan. Venus, (Japanese Journal of Malacology), 55(2) : 91-95.

Other photos of Gymnodoris striata :

Armand Daydé Reunion, Etang Salé les bains lagoon, 1 m, 7 October 2009, during the night, size : 40 mm The body is translucent white to pale creamly yellow with bright yellow orange to orange longitudinal ridges (a) The notal brim (b) and foot (c) margins are the same color The sides of the body also bear orange ridges (d)

The gills are arranged in a transverse row across the back in this species. They are translucent white with a orange line up their front axis. Gills branches are flattened and leaf-like

Christophe Cadet Reunion, Etang Salé les bains lagoon, 1 m, 25 October 2010, during the night, size : 30 mm Specimen out of the sand...

Christophe Cadet Reunion, Etang Salé les bains lagoon, 1 m, 25 October 2010, during the night, size : 30 mm The second specimen found during this night... The genital aperture (a), on the right side.

	Crawling on the substrate...
And now, burrowing into the sand...

Antoine Legrand Mayotte LPasse en S buoy 6, 12 m size 20 mm, April 2019

Mauritius, Analogium striatum, at La Gaulette, by Pierre Périès