Synonyms: (basyonim) Melobesia corallinae P. & H. Crouan (1867) p. 150; Lithophyllum corallinae (P. & H. Crouan) Heydrich (1897) p. 47; Dermatolithon corallinae (P. & H. Crouan) Foslie d’après Børgesen (1903) p. 402; Lithophyllum pustulatum f. corallinae (P. & H. Crouan) Foslie (1905) (3) p. 118,127; Lithophyllum macrocarpum f. corallinae (P. & H. Crouan) Foslie (1909) (2) p. 47.

VEGETATIVE FEATURES

Thallus habit: encrusting, flattened and closely adherent or attached by a central basal crust therefore with free margins (B). Smooth surface. Size: diameter up to 6mm; thickness up to 0.3mm. Colour of living specimen: from reddish to brown violet. Colour of dried specimen: mauve.

Basal filaments: unilayered, palisade cells, oblique and sinuate often growing thin at the base, or short and vertically orientated: 7-16µm long x 7-98µm in diameter. Erect filaments: up to 20 cells long, usually laterally aligned: 10-63µm long x 5-20µm in diameter. Epithallial cells: single, convex (B). Cell connections: secondary pit-connections. Other features: trichocytes occasionally present..

Gametangial conceptacles: spermatangial immersed; triangular chambers (78-130µm in diameter x 39-52µm high); carpogonial conceptacles immersed, flask-shaped chambers (90-104µm in diameter x 39-59µm high). Tetrasporangial conceptacles: unknown. Bisporangial conceptacles : uniporate, completely immersed to slightly raised and clearly recognizable as a pinkish dome surrounded by a white circle (C); rounded to elliptical chambers: 169-235µm in diameter x 75-117µm high. Phenology: ---

Habitat: epiphytic, mainly on Corallina officinalis, occasionally on C. elongata or on Haliptilon species; common in littoral pools. Bathymetric distribution: littoral. Geographic distribution (Babbini & Bressan 1997):

Western Mediterranean Sea (African shores) (B): Tunisia; Middle Western Mediterranean Sea (C): Spain, Italy; North Western Mediterranean Sea (D): Spain; North Adriatic Sea (E): Slovenia, Croatia; Middle Adriatic Sea (F): Italy, Croatia; South Adriatic Sea (G): Italy; South Eastern Mediterranean Sea (H): Italy, Libya; Middle Eastern Mediterranean Sea (L): Greece; North Eastern Mediterranean Sea (M): Greece.