Doris cf pecten Collingwood, 1881

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This species has been observed on Reunion and Madagascar Islands


Order : Nudibranchia
Suborder : Euctenidiacea
Superfamily : Doridoidea
Family : Dorididae
Distribution : Réunion, ...
Maximal size : 10 mm
Abundance : Seldom on the reef flat zone

Species characteristics :

They are characterised by the arrangement of the gills in a transverse line across the back. There is a dorsal flap covering the gill opening

The raised central region is usually paler, almost translucent in colour, with a criss-cross pattern caused by the underlying spicules in the skin

Mantle covered with numerous small pustules, some higher in the axis of the back

The mantle is blue-green, to dark blue-green

Doriopsis cf granulosa
Showing species characteristics...

Photo Christophe Cadet
Reunion, Etang salé, on the rocky coast, less 1 m, 22 January 2011, size : 7 mm

See more about : Sightening and mating periods

Remarks :

Identification confirmed by Nathalie Yonow
    Specimens of Doriopsis are either deep blue, green or yellow and there has been considerable confusion in the literature concerning how many species there are in the genus. At one extreme 4 species, one each of green and blue and two of yellow have been suggested, while at the other extreme only one variably coloured species has been proposed
    Biological observations from throughout the Pacific suggest that there are at least two species, one yellow or green (Doriopsis granulosa) and one deep blue (Doriopsis pecten).
    According Gosliner, species with pectinate gills where often placed in a separate genus, Doriopsis, but are now considered to be a subgroup within Doris. Doris granulosa and Doris pecten....
    In Reunion Island we found a strange specimen called for the moment Doris cf pecten. This specimen eats a yellow sponge like D. granulosa, but have a blue criss cross pattern like D. pecten !!!!

 

Doris granulosa

Doris cf pecten

Doris pecten

Size

38 mm (18 to 25 is usual for adult)

10 mm

16 mm (7 to 8 mm is usual for adults)

Dorsum

All the mantle is covered in evenly sized low rounded tubercles

Mantle covered with numerous small pustules, some higher in the axis of the back (or dirt often cling)

 

The raised central region is usually paler, almost translucent in colour, with a criss-cross pattern caused by the underlying spicules in the skin

Colour

It ranges in colour from a pale yellow-orange to a dark green

The mantle is blue-green to dark blue-green.

The mantle is blue, sometimes so dark are to appear almost black

Food

Found feeding on a yellow or orange sponge, which is probably Prianos phlox

Found feeding on a yellow or orange sponge

Found feeding exclusively on a deep blue sponge Terpios

 

Spawn

The eggs are reported to be yellow and is much larger, and sturdier.

 

The eggs are reported to be cream to white with a frilly edge, and quite small and delicate

Bibliographic data :

They are characterised by the arrangement of the gills in a transverse line across the back rather than in the typical dorid circle. There is a dorsal flap covering the gill opening
    The body feels very firm because the skin is toughered with tiny rods (spicules) and the mantle is rough to the touch
    The rhinophores and gills are the same colour of the body without any speckling
    The 8 to 10, simple gills for a circlet around the anus that is compressed into a rearward-projecting fan overstopped by a notal flap
    Found under stones and rubble from the intertidal zone to a about 3 m depth where its feeds on yellow sponge...

References :

Bill Rudman Seaslug site : Sea Slug Forum : Doriopsis granulosa and Doriopsis pecten

Publications :

Baba, K. & Hamatani, I., 1961. On two new species of Doriopsis (syn. Ctenodoris ) from Japan (Nudibranchia - Dorididae). Publications of the Seto Marine Biological Laboratory, 9 : 63-65.
    Bertsch, H. & Johnson, S., 1981. Hawaiian Nudibranch s. Honolulu: Oriental Publishing Co
    Collingwood, C. (1881). On some new species of nudibranchiate mollusca from the Eastern Seas. Transactions of the Linnean Society, London, Zoology, 2 : 123-140, Pls 9-10.
    Hamatani, I, 1961. Notes on veligers of Japanese opisthobranchs(4). Publications of the Seto Marine Biological Laboratory, 9(2) :353-361
    Johnson, S., 1981. Blue camouflage in a nudibranch. Hawaiian Shell News, 29(6) : 14
    Kay, E.A. & Young, D.K., 1969. The Doridacea (Opisthobranchia: Mollusca) of the Hawaiian Islands. Pacific Science, 23 : 172-231
    Pease, W.H. (1860). Descriptions of new species of mollusca from the Sandwich Islands. Proceedings of the Zoological Society of London, 28 : 18-37
    Young, D.K., 1967. New records of Nudibranchia from the Central and West-Central Pacific with a description of a new species. The Veliger, 10 : 159-173

Other photos of Doris cf pecten :


Christophe Cadet       

Reunion, Etang salé lagoon, less 1 m, 15 December 2010, size : 8 mm

The 8 to 10, simple gills for a circlet around the anus that is compressed into a rearward-projecting fan (a) overstopped by a notal flap (b)

Mantle covered with numerous small pustules, some higher in the axis (c) of the back

No criss-cross pattern caused by the underlying spicules in the skin of this specimen


 

 

Christophe Cadet

Reunion, Etang salé lagoon, less 1 m, 15 December 2010, size : 10 mm

3 specimens, in a yellow sponge, with their spawn ???

The spawn consists of a cream coil of 3 or 4 whorls

 


Eva Fontaine

Reunion, Etang salé lagoon, less 1 m, 9 November 2008, size : 5-6 mm

This small specimen clearly eats voraciously this yellow sponge...


 

 

Christophe Cadet

Reunion, Saint Leu lagoon, less 1 m, 26 January 2010, size : 6 mm

 

Specimen with the criss-cross pattern (a) caused by the underlying spicules in the skin.


Christophe Cadet

Reunion, l'Ermitage lagoon, less 1 m, 2 February 2012, size : 5 mm

 

 

Blue green and green patterns...


 

 

Alain-Benoît Rassat

Madagascar, Nosy bé, charlie point, 16 m, 19 May 2016, size : 20 mm

 

 

 


 More photos from Indian Ocean

Reunion, Doris cf pecten with its spawn (?), at Etang salé, by Christophe Cadet

Reunion, two Doris cf pecten eating a yellow sponge, at Etang salé, by Eva Fontaine