This species has been observed on
Mayotte, Mohéli and Madagascar Islands
Order : Nudibranchia
Suborder : Euctenidiacea
Superfamily : Doridoidea
Family : Discodorididae
Distribution : Indian Océan
Maximal size : 45 mm
Abundance : Seldom on the fore
Species characteristics :
The indian Ocean individual has bright opaque white
tubercles with orange spots on the tips and a translucent white ground
colour covered in a dusting of tiny orange dots.
There is an orange margin around the foot and a yellow
one around the mantle.
Black is present on the gills as lines, and a black
line is found posteriorly on the rhinophore stalk and fades towards the
sides. The rhinophore lamellae are mostly black.
Nosy Bé, patate de l'entrée, 14 m, 21 March 2014, size : 30 mm
See more about :
Sightening and mating periods
According Yira Tibiçriça "I
don’t think there is an easy answer for this one. The color of
rhinophores and gills are different from H. nuarrensis and it is missing
the dots and does look more yellow and missing the bluish ring around
the tubercles, so most likely not BUT Halgerda spp are highly variable
so we can’t be sure about anything until we study the specific
morphotype" so I used the term of cf. nuarrensis....
Under the name Halgerda sp. 3 in "Nudibranch
and Sea Slugs identification, Gosliner, Valdès and Behrens, 2015"
According Bill Rudman : " All the western
Indian Ocean animals, including yours, show the black on the gills and
rhinophores as lines, while animals from the Pacific have black
spots, so the two may turn out to be distinct species."
According Nathalie Yonow : " It differs
from H. carlsoni in the colour of its gills
and rhinophores. Indian Ocean individuals (additional photographs
available on various websites) have much more black pigment : the black
is present on the gills as lines, and a black line is found posteriorly
on the rhinophore stalk and fades towards the sides. The rhinophore
lamellae are mostly black. Halgerda carlsoni has
black speckling only on the gills and rhinophores, and a row of orange
spots along the edge of the mantle (not a continuous line)."
Bill Rudman Seaslug site : Sea Slug Forum : Halgerda
Y., Pola, M. & Cervera J.L. (2018). Systematics of the genus Halgerda
Bergh, 1880 (Heterobranchia : Nudibranchia) of Mozambique with
descriptions of six new species. Invertebrate Systematics.
Other photos of Halgerda nuarrensis
Madagascar, Ile de Sainte
Marie, 15-20 m, October 2008, size : 20-40 mm
Black is present on the gills as lines (a)
Mayotte, 10 March 2007
Mohéli, Ouallah, 18 October
2006, size : 30 mm
Madagascar, Baie d’Antongil,
10 m, 21 September 2017
A mating event..
More photos from