Français English

Roccella tinctoria DC Taxon Atlantique-Ouessant Cf.

Synonyms:

Family: ROCCELLACEAE

Habitat: Xeric supralittoral  zone

Description

     Thallus usually erect and tufted, to 3-5 cm high and 5-8 cm across, branches more or less terete, 1-3 mm diam., arising from a holdfast, outer brownish and inner side dull whitish, apices pointed, surface smooth often with soralia, soralia rounded and pustulose at first, becoming globose, whitish, branches pale grey, greyish tinged with purple, grey-brownish, etc., never brown-reddish, medulla white. Apothecia scarce, marginal, 1-2 mm diam., black. Ascospores 3-septate, 23-27 x 6-8 µm. Photobiont: Trentepohlia. Cortex and medulla K+/- yellow, C+ instantly carmine. Rare, saxicolous, thermophile and Macaronesian, on vertical walls of foreshore rocks in the S-W of Ouessant island. N.B. Not to be confused with Roccella phycopsis that grows together but the C+ carmine reaction is not immediate for the latter, its medulla is yellow-orange towards the base (but this is not a hallmark). Intermediate taxa between the two species seem to grow in the Finistère (still under investigation) and we cannot exclude that it is a chemotype of Roccella phycopsis since it clearly appears different from Mediterranean taxa from Corsica subjected to different climatic conditions and above all mahogany. See Roccella tinctoria Méditerranée-Corse.
As a consequence, the present description is merely provisional, see Roccella phycopsis forma.

Tehler A., Dahlkild A., Eldenäs P. & Feige G.B. 2004. The phylogeny and taxonomy of Macaronesian, European and Mediterranean Roccella (Roccellacea, Arthoniales). Acta Univ. Ups. Symb. Bot. Ups. 34:1, 405-428. 







Roccella tinctoria Atlantique Ouessant Habitat Ouessant 1
Bernard BOUFFINIER



Roccella tinctoria Atlantique Ouessant Ouessant 2
Bernard BOUFFINIER



Roccella tinctoria Atlantique Ouessant Ouessant 3
Bernard BOUFFINIER



Roccella tinctoria Atlantique Ouessant Ouessant 4
Bernard BOUFFINIER



Roccella tinctoria Atlantique Ouessant Ouessant 5
Bernard BOUFFINIER



Roccella tinctoria Atlantique Ouessant Ouessant 6
Bernard BOUFFINIER



Roccella tinctoria Atlantique Ouessant Ouessant 7
Bernard BOUFFINIER



Roccella tinctoria Atlantique Ouessant Ouessant 8
Bernard BOUFFINIER



Roccella tinctoria Atlantique Ouessant Ouessant 9
Bernard BOUFFINIER



Roccella tinctoria Atlantique Ouessant Ouessant 10
Bernard BOUFFINIER



Roccella tinctoria taxon Atlantique-Ouessant Cf. Ouessant 11
Jacques HAINE



Roccella tinctoria taxon Atlantique-Ouessant Cf. Ouessant 12
Jacques HAINE



Roccella tinctoria taxon Atlantique-Ouessant Cf. Ouessant 13
Jacques HAINE



Roccella tinctoria taxon Atlantique-Ouessant Cf. Coupe apothécie eau & K Ouessant 14
Jacques HAINE



Roccella tinctoria taxon Atlantique-Ouessant Cf. Asques jeunes Eau & K Ouessant 15
Jacques HAINE



Roccella tinctoria taxon Atlantique-Ouessant Cf. Asques Bleu Coton Ouessant 16
Jacques HAINE



Roccella tinctoria taxon Atlantique-Ouessant Cf. Spores matures eau Ouessant 17
Jacques HAINE



Roccella tinctoria taxon Atlantique-Ouessant Cf. Spores Bleu Coton Ouessant 18
Jacques HAINE



Roccella tinctoria Taxon Atlantique-Ouessant Cf. Coupe apo Ouessant 19
Jacques HAINE



Roccella tinctoria Taxon Atlantique-Ouessant Cf. Asques Lugol Ouessant 20
Jacques HAINE



Return
Content : Alain Gérault - Website development : Sylvain Ard - Hosting : Online.net