Pseudobiceros cf gratus (Kato, 1937)

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


Order : Polycladida
Suborder : Cotylea
Superfamily : Pseudocerotoidea
Family : Pseudocerotidae
Distribution : Indo Pacific
Maximal size : 50 mm
Abundance :


Species characteristics :

Background body colour cream to grey with two median black to grey stripes joining posteriorly and anteriorly

Marginal black band, with fade inner grey band

The black pseudotentacles are pointed, ear-like with white tips

Pseudobiceroscf gratus
Showing species characteristics...

Photo Philibert Bidgrain
Reunion, Etang salé lagoon, less 1 m, 3 December 2009, size : 35-40 mm

See more about : Pseudobiceros cf gratus variability in Southwest Indian ocean

See more about : The flatworm and the sea urchin...

Remarks :

This species looks like Pseudobiceros gratus but there are some obvious differences :
            - Background body with two median black stripes in Pseudobiceros cf gratus. Body with three or four wide black or grey longitudinal stripes in P. gratus
            - Marginal band black, with fade inner grey band in P. cf gratus, and only a narrow black margin in P. gratus
   For some people it was only a variation of P. gratus. Newman (2003), considered this species as a different species (Pseudobiceros sp 15)

Bibliographic data :

Habitat : Found under rubble on the reef crest and slope
   Ethymology : gratus = pleasing for its pleasant colour pattern

References :

Discover life : Pseudobiceros gratus
   Marine flatworms of the world : Pseudobiceros gratus sp 1
   Nudipixel : Pseudobiceros gratus

Publications :

Kato, K. (1937). Polyclads collected in Idu, Japan. Japanese Journal of Zoology 7: 211–232
    Newman, L.J. & Cannon, L.R.G. (1997). Nine new Pseudobiceros (Platyhelminthes, Polycladida, Pseudocerotidae) from the Indo-Pacific. The Raffles Bulletin of Zoology 45: 341–368
    Newman, L.J. & Cannon, L.R.G. (2003). Marine Flatworms: the world of Polyclads. CSIRO Publishing : Melbourne 112 p

Other photos of Pseudobiceros cf gratus :


Philibert Bidgrain

Reunion, "Plage de la gendarmerie", Saint Pierre, less 1 m, 21 December 2009, size : 25 mm

The head region showing the cerebral eyes spot (a) and the black pointed pseudotentacles, ear-like with white tips (b)


 

 

Eva Fontaine

Reunion, Trou d'eau lagoon, less 1 m, 5 December 2009, size : 30-35 mm

In some specimens we can observed some opaque white dots (a) all over the body.

 


 

 

Philibert Bidgrain

Reunion, Etang salé on the rocky coast, less 1 m, 15 May 2006, size : 18 mm

A small specimen with a brown-orange pale coloration on the pseudotentacles.


 

Marina Poddubetskaia

Mauritius, "Gaetan Patchers", Pereybère, 14 m, 17 October 2002, size : 40 mm

This specimen is one of the specimen use to illustrate the diversity of this species under the name of Pseudobiceros sp 15 by Leslie Newman in "Fabulous flatworms, a guide to marine polyclads"


 

Philibert Bidgrain

Reunion, Etang salé lagoon, less 1 m, 3 December 2009, size : 35-40 mm

Marginal black band (a), with fade inner grey band (b)

Body elongated oval, with a highly ruffled margin


Philibert Bidgrain

Reunion, Etang salé lagoon, less 1 m, 3 December 2009, size : 35-40 mm

Two photos of the same specimen... with a highly ruffled margin


 

Philibert Bidgrain

Reunion, Trou d'eau lagoon, less 1 m, 3 December 2009, size : 6 mm

A juvenile, 6 mm long


 

 

Christophe Cadet

Reunion, L'ermitage lagoon, less 1 m, 27 December 2010, size : 25 mm

A strange specimen with bifide (a) median black to grey stripes.

 


Philippe Bourjon

Réunion, Hermitage, less 1 m, 27 September 2014, size : 20 mm

The underside is grey wwith a black marginal border


 More photos from Indian Ocean

See more about : Pseudobiceros cf gratus variability in Southwest Indian ocean

See more about : The flatworm and the sea urchin...

Reunion, Pseudobiceros cf gratus with deep cream coloration, at Saint Leu, by Eva Fontaine

Reunion, two Pseudobiceros cf gratus, at La Saline, by Thierry Mulochau 

Reunion, Pseudobiceros cf gratus with deep black bands, at La Saline, by Christophe Cadet

Madagascar, Pseudobiceros cf gratus, at Nosy bé, by Alain-Benoît Rassat