Cuthona sp2

Version française...

This species has been observed on Reunion and Madagascar Islands


Order : Nudibranchia
Suborder : Dexiarchia
Superfamily : Fionoidea
Family : Fionidae
Distribution : Western Pacific of Australia, Papouasie New Guinea, Southern Japon and now Réunion Island
Maximal size : 15 mm
Abundance : Seldom if ever... on the fore reef zone


Species characteristics :

Both the rhinophores and oral tentacle have opaque white dots and an orange apical half

Anterior face of cerata opaque white cream while the posterior side is pale orange. Apex light purple to whitish as in the base of oral tentacle

Body whitish with dense markings of opaque white

Cuthona sp2
Showing species characteristics...
Photo Sully Bachel
Reunion, La Possession, Ravine à Jacques, 6 m, 15 December 2009, size : 10-12 mm

See more about : Sightening and mating periods
   See more about : Cuthona sp2 variability in Southwest Indian ocean

Remarks :

Identification confirmed by Nathalie Yonow and Hsini Lin
    Under the name of Cuthona sp. 16 and/or Cuthona sp. 18 in "Nudibranch and Sea Slugs identification, Gosliner, Valdès and Behrens, 2015". Probably the same species , just a problem of size and variability...
    According Hsini Lin this species should be called Tenellia sp. 2 (see : Cella K, Carmona L, Ekimova I, Chichvarkhin A, Schepetov D, et al. (2016))
    For some author this species belong to genus Trinchesia, and called it Trinchesia sp. 2

Bibliographic data :

In Cuthona like other Cuthona, cnidosac are present at the apex of the cerata...
    This aeolid looks like :
                - Cuthona sp1, but in Cuthona sp1, the rhinophores are white with a bright red medial band, and cerata have a spot of bright red on the cream area
                - Cuthona kanga, but in Cuthona kanga, the cerata has a terminal opaque whitish tip and just below an yellowish-orange. Then a bright ultramarine blue and a dull green colouration due to the digestive gland duct.

References :

Publications :

Cuthona sp 18 in : Gosliner,T.M.; Behrens,D.W.; Valdés,A (2015) Indo-pacific nudibranchs and seaslugs A field guide to the World's most diverse fauna
    Cella K, Carmona L, Ekimova I, Chichvarkhin A, Schepetov D, et al. (2016) A Radical Solution: The Phylogeny of the Nudibranch Family Fionidae. PLOS ONE 11(12): e0167800

Other photos of Cuthona sp. 2 :

Alain-Benoît Rassat

Madagascar, Nosy bé, 13 Jully 2017

Looks like more Cuthona sp. 16 in "Nudibranch and Sea Slugs identification, Gosliner, Valdès and Behrens, 2015"

Alain-Benoît Rassat

Madagascar, Nosy bé, 26 September 2017

Looks like more Cuthona sp. 18 in in "Nudibranch and Sea Slugs identification, Gosliner, Valdès and Behrens, 2015"

 

Sully Bachel


Reunion, La Possession, Ravine à Jacques, 6 m, 15 December 2009, size : 10-12 mm

Both the rhinophores (a) and oral tentacle (b) have opaque white dots and an orange apical half

Anterior face of cerata opaque white (d) while the posterior side is pale orange (e). Apex light purple (c) as in the base of oral tentacle

 

Sully Bachel


Reunion, La Possession, Route en corniche, 8 m, 28 February 2010, size : 15-20 mm

A specimen with a cerata whitish apex (a) coloration

Body whitish (b) with dense markings of opaque white

Sully Bachel


Reunion, Port de la Possession, 14 m, 20 March 2010, size : 8-12 mm

3 specimens were found during this dive....

Anterior face of cerata opaque white cream while the posterior side is pale orange (a)

A specimen with a cerata whitish apex coloration

Sully Bachel


Reunion, Port de la Possession, 14 m, 20 March 2010, size : 8 mm

3 specimens were found during this dive....

Presence of diffuse orange coloration on the rhinophores (a) and the oral tentacle (b) of this small specimen

a classical apical orange band with an extra basal orange band... on the rhinophores

 

 More photos from Indian Ocean

See more about : Cuthona sp2 variability in Southwest Indian ocean

Madagascar, Cuthona sp2, at Nosy Bé, by Alain-Benoît Rassat