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This species has been observed on Reunion, Mauritius, Rodrigues, Mayotte, Madagascar and Seychelles

Order : Nudibranchia Suborder : Euctenidiacea Superfamily : Onchidoridoidea Family : Goniodorididae Distribution : This species has been reported from Japan, Indonesia, Fiji, Tanzania, Kenya, Reunion, Rodrigues Island, the Maldives and Northwest Australia Maximal size : 20 mm Species characteristics : The body is white and nearly transparent. There are large blotches of black pigment arranged somewhat symmetrically along the sides of the dorsum and one patch on the anterior side of the foot    The anterior head tentacles are white    The oral tentacles are dark brown or black    Black rhinophores with black extra-rhinophoral appendages    Black gills with black and white extra-branchial appendages
	Showing species characteristics...	Photo Richard Lai Cheong "Trou aux Biches" at Mauritius, 9 June 2008, size : 15 mm

See more about : Sightening and mating periods

Remarks :

Identification confirmed by Bill Rudman
    Synonymous : (according Worms)
          - No other name

Bibliographic data :

The specific name naeva is from the Latin word meaning ‘mole' or ‘birthmark' to describe the large blotches of black pigment on the dorsum of this species.
    The head is rounded anteriorly and the anterior foot margin is extended into elongate tentacles. The anterior head tentacles are white.
    The oral tentacles are short and cylindrical with a curved apex. They are dark brown or black.
    The non-retractile, perfoliate rhinophores are relatively short with 12–14 lamellae. The rhinophores leaves are dark brown or black.The apex of the rhinophores is simply rounded without an extended appendage. The extra-rhinophoral appendages are relatively short and have a curved apex. The extra-rhinophoral appendages is the same dark brown or black as the oral tentacles.
    The gill consists of three tripinnate branches. The gill leaves are dark brown or black The extra-branchial appendages are nearly upright and stout. The extra-branchial appendages is the same dark brown or black as the oral tentacles. The base of the extra-branchial appendages however, is white.
    Species of Trapania seem to feed on kamptozoa (=Entoprocta),
    - T. naeva closely resembles T. darvelli in that it has a white body with dark brown to black pigment on the gill leaves, the rhinophores, the oral tentacles and on the extra-branchial and extra-rhinophoral appendages. But T. naeva differs markedly in having large black patches over the surface of the body.
       - There are external similarities with T. japonica and with T. goslineri . All three species have large dark pigment spots on the dorsum. However, T. japonica has bright yellow lateral appendages and T. naeva has dark appendages. T. goslineri has black streaks in addition to the spots.

References :

Bill Rudman Seaslug site : Sea Slug Forum : Trapania naeva
   Nudipixel Trapania naeva

Publications :

Gosliner, T.M. & Fahey, S.H. (2008)  Systematics of Trapania (Mollusca: Nudibranchia: Goniodorididae) with descriptions of 16 new species Systematics and Biodiversity , 6 (1): 53-98

Other photos of Trapania naeva :

Photo Richard Lai Cheong "Trou aux Biches" at Mauritius, 9 June 2008, size : 15 mm    The head is rounded anteriorly and the anterior foot margin is extended into elongate tentacles. The anterior head tentacles are white. The oral tentacles are short and cylindrical with a curved apex. They are dark brown or black. The non-retractile, perfoliate rhinophores are relatively short with 12–14 lamellae. The rhinophores leaves are dark brown or black.The apex of the rhinophores is simply rounded without an extended appendage. The extra-rhinophoral appendages are relatively short and have a curved apex. The extra-rhinophoral appendages is the same dark brown or black as the oral tentacles. Underside of this seaslug :

Emmanuel Eby Rodrigues, in "Passe de l'anse Mourouk", 11 September 2004 A spawning event for this species?

Patrick Millar Mauritius, dive site "7 Patches", 10 m, 18 August 2007, size : 25 mm

 More photos from Indian Ocean

 Mayotte, Trapania naeva, at Longoni Harbour, by Yvon Gildas

Reunion, the first Trapania naeva, at Cap la Houssaye, by Christophe Jammes  

Reunion, the second Trapania naeva, at Cap la Houssaye, by Monika Bachel 

Madagascar, Trapania naeva, at Nosy Bé, by Alain-Benoît Rassat

Seychelles, Trapania naeva, at Mahé, by Christophe Mason-Parker