Thorunna africana Rudman, 1984

Version française...

This species has been observed on Mayotte and Madagascar Island

Order : Nudibranchia
Suborder : Euctenidiacea
Superfamily : Doridoidea
Family : Chromodorididae
Distribution : Tanzania, Kenya, Red Sea, Andaman Sea and Madagascar.
Maximal size : 20 mm
Abundance : Seldom if ever on the fore reef zone

Species characteristics :

The body is white with a bright yellow border to the mantle.

The simply pinnate gills and rhinophores have red midribs and may have red edges on the lamellae.

thorunna africana
Showing species characteristics...
Photo Alain-Benoît Rassat
Madagascar, Nosy bé, plateau des Arches, 17 m, 15 December 2012, size : 15-20 mm

See more about : Sightening and mating periods

Remarks :

Identification confirmed by Nathalie Yonow and Hsini Lin
    Synonymous : (according Worms)
          - No other name

Bibliographic data :

The body is relatively high and elongate with a narrow mantle overlap which is sometimes thrown into three major folds down each side of the body.
    It feeds on Dysidea sp
    The rhinophore is white with a red line along the anterior and posterior midline of the club.
    The gills are simple, forming a circle around the anus. They wave rhythmically when the animal is crawling. The outer edge of the white gills is also red and sometimes the upper half or third of the inside edge is also red.
    Species of Thorunna are quite small, for chromodorids, and one characteristic feature is that the gills are held upright in a goblet-shaped group, and they wave rhythmically as the animal crawls along.
    Similar in color and shape to Thorunna furtiva but T. africana has :
            - in having a yellow mantle border
            - and a red edging to gills and rhinophores.
T. furtiva, present in the western pacific has an orange border to the mantle and orange edging to the rhinophores and outer edge of each gill

References :

Bill Rudman Seaslug site : Sea Slug Forum : Thorunna africana
   Nudipixel Thorunna africana

Publications :

Johnson R.F. & Gosliner T.M. (2012) Traditional taxonomic groupings mask evolutionary history: A molecular phylogeny and new classification of the chromodorid nudibranchs. PLoS ONE 7(4): e33479.
    Rudman, W.B. (1984) The Chromodorididae (Opisthobranchia: Mollusca) of the Indo-West Pacific: a review of the genera. Zoological Journal of the Linnean Society 81 : 115-273.
    Rudman, W.B. (1985) The Chromodorididae (Opisthobranchia: Mollusca) of the Indo-West Pacific: Chromodoris aureomarginata, C. verrieri and C. fidelis colour groups. Zoological Journal of the Linnean Society 83 : 241-299

Other photos of Thorunna africana :

Frédéric Ducarne

Mayotte, 2018


Jean Roger

Mayotte, Plage du Faré, less 1 m, 20 January 2018


Barbara Bini

Madagascar, Nosy bé, 20 m, size : 20 mm



 More photos from Indian Ocean

If you have taken a photo of this species in South West Indian Ocean, please Contact us...