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37 Jorunna tomentosa album. Comparison image of Jorunna onubensis.

Close-up image of mantle of Jorunna onubensis. Found under a stone at 14 m depth. Cadaqués, Catalonia. October 2007. © M. Pontes.

A: Crowded, match-like, retractile tubercles with subapical ring of sharp projecting spicules (caryophyllidia). Found on both J. tomentosa and J. onubensis. Difficult to photograph because small and transparent-colourless.

The bright white opaque cap on some of them is mentioned in the original description of J. onubensis as 'iridescente'; no iridescence can be seen in this image, but the camera may not have captured it. The white caps appear to be quite frequent on the caryophyllidia of J. onubensis, but some specimens of J. tomentosa also have some white caps.

 

Jorunna onubensis Cervera, García-Gómez & García, 1986,

is very similar to J. tomentosa; reliable identification of this species requires examination of dissected anatomical features and, ideally, D.N.A sequencing. The external features below are described in the original description of J. onubensis [based on four intertidal specimens from Huelva, southern Spain]. The features illustrated in this Flickr account are on a specimen from Catalonia of J. onubensis identified by Miquel Pontes and confirmed by Prof. J. Lucas Cervera. Many features are common to both J. onubensis and J. tomentosa; confirmation by dissection and/or D.N.A, sequencing is desirable. Specimens of J. onubensis photographed by one of the authors of its first published description, J. C. García Gómez, can be seen at opistobranquis.info/en/guia/nudibranchia/euctenidiacea/do...

and other images by L. Sánchez-Tocino at

wpd.ugr.es/~litoraldegranada/el-litoral/el-litoral-sumerg...

It has been recorded from Spain, Portugal, Madeira and the Canary Islands.

 

FULL 9 POINT COMPARISON with J. tomentosa:

Jorunna onubensis

1: 12mm to 18mm long (four specimens March & April 1984). Up to 55mm long (Sánchez-Tocino, accessed February 2018).

2: Light brown, often slightly pinkish 34Jt flic.kr/p/FQyhy5 [sometimes grey?]. Sometimes with dark, greyish or greyish-brown, blotches of varying size. Small opaque white marks near periphery of mantle 36Jt flic.kr/p/22B7b8M

3: Crowded, match-like, retractile tubercles with skirt of sharp projecting spicules (caryophyllidia), similar to J. tomentosa, some with opaque, bright-white apex ['il mantello è ricoperto da tubercoli cariofillidei molto

fitti. Questi sono circondati da 6-7 spicole le cui estremità sorpassano generalmente la sommità dei tubercoli. A volte le estremità delle spicole rimangono allo stesso livello dei tubercoli e in altri casi ne rimangono al di sotto. - - - Alcuni dei tubercoli dorsali persentavano il loro apice di colore bianco iridescente'.]

4: The translucent, almost colourless, gills have a fine brown punctuation, hardly distinguishable to the naked eye 38Jt flic.kr/p/22B7aQx & 39Jt flic.kr/p/22B7a9H . The end of the anal papilla is brown with whitish striations that subdivide it into unequal parts 38Jt flic.kr/p/22B7aQx .

5: Base of extended gills surrounded by collar-like sheath 39Jt flic.kr/p/22B7a9H which closes over the gills when they are retracted into a pit 35Jt flic.kr/p/22B7bHp

6: Slender tapered oral tentacles, similar to J. tomentosa.

7: Convex body with raised profile, similar to J. tomentosa.

8: Short rhinophores are whitish, sometimes with strip of dark brown subapically. Basal stem transparent. About 15 lamellae form conical distal half.

9: Posterior of foot protrudes slightly when in motion.

 

Jorunna tomentosa

1: Length up to 30 mm (Neuhaus et al, 2021), 55 mm (Thompson and Brown, 1984), often a similar size to Doris pseudoargus.

2: Dorsally, sandy-brown 1Jt flic.kr/p/EjpcXr , reddish brown, grey-white, grey-cream, yellow 2Jt flic.kr/p/K2ALfV , yellow cream 3Jt flic.kr/p/EjpceH , buff-orange, or white 4Jt flic.kr/p/K2AJ14. Small opaque white glandular structures near periphery of mantle 3Jt flic.kr/p/EjpceH but sometimes not discernible 1Jt flic.kr/p/EjpcXr . Usually, scattered small dark spots and a few dark blotches in a longitudinal row on each side 5Jt flic.kr/p/EjpbfP ; sometimes blotches absent, or few and small 11Jt flic.kr/p/22B75ok and occasionally the small spots are absent.

3: Mantle has crowded, small, match-like, retractile tubercles (caryophyllidia) 8Jt flic.kr/p/K2AFXB with a ring of sharp projecting spicules surrounding the rounded apex. Body has velvety appearance and soft feel.

4: Large yellow-cream to grey gills around brown anal papilla 2Jt flic.kr/p/K2ALfV & 4Jt flic.kr/p/K2AJ14 . Gills are often paler than the mantle and sometimes have dark dots.

5: Base of extended gills surrounded by distinct collar-like sheath 9Jt flic.kr/p/22B7oGe which closes over the gills when they are retracted into a pit 12Jt flic.kr/p/22B7nRM .

6: Slender tapered oral tentacles 15Jt flic.kr/p/K2AEjX .

7: Convex body with raised profile 7Jt flic.kr/p/22B7pn2 .

8: Short, stout rhinophores have a translucent whitish, or slightly tinted, basal stem and a conical, lamellated, yellow-cream to grey, distal part bearing red to brown pigment dots/marks 8Jt flic.kr/p/K2AFXB .

9: Posterior of foot protrudes when in motion 19Jt flic.kr/p/22B7iPD .

 

 

Full SPECIES DESCRIPTION: flic.kr/p/K2ALfV

Key id. features: flic.kr/p/EjpcXr

Sets of OTHER SPECIES:

www.flickr.com/photos/56388191@N08/collections/

 

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Uploaded on February 1, 2018
Taken on October 27, 2007