Bacidia sipmanii M. Brand, Coppins, van den Boom & Sérus.
Bibl. Lichenol., 99: 90, 2009.
Distribution: N - Lig (Brand & al. 2009).
Description: Thallus crustose, episubstratic, pale green-grey to grey-brown,< 0.3 mm thick, smooth to slightly rugose, continuous to rimose, sometimes delimited by a whitish prothallus. Apothecia lecideine, 0.4-1.3 mm across, with a flat to convex, pale to medium (red-)brown disc and a usually darker, sometimes white-pruinose, often finally excluded proper margin. Proper exciple of radiating, strongly conglutinated, thick-walled hyphae with narrow lumina, the outer cells with brown-pigmented walls, to c. 5 µm wide; epithecium brownish; hymenium colourless, 40-60 µm thick; paraphyses simple or branched in upper parts, rather conglutinated, 1-1.5 µm thick at mid-level, the apical cells slightly swollen, to 2.5 µm wide; hypothecium colourless, except upper part (subhymenium) which is usually pale red-orange. Asci 8-spored, clavate to cylindrical-clavate, the apical dome K/I+ dark blue with a pale, conical-pointed apical cushion (axial mass), the wall K/I-, but the thin outer gel K/I+ blue, Bacidia-type. Ascospores (1-)3-7-septate, hyaline, bacilliform to acicular, slightly tapering towards one end, 26-40 x 1.5-2.5 μm. Pycnidia immersed, pale orange-brown. Conidia filiform, aseptate, strongly curved, (22-)23-25(-27) μm long. Photobiont chlorococcoid. Spot tests: thallus K-, C-, KC-, P-, UV-. Chemistry: thallus without lichen substances; exciple and pycnidial wall wih the rubella-orange pigment.
Note: a Mediterranean-Macaronesian species of siliceous, maritime rocks in the xeric-supralittoral zone, where it usually occurs in crevices and underhangs.