Lithophyllum corallinae (P.Crouan & H.Crouan) Heydrich, 1897: 47

Tâmega, Frederico T. S., Riosmena-Rodriguez, Rafael, Mariath, Paula Spotorno-Oliveira Rodrigo, Khader, Samir & Figueiredo, Marcia A. O., 2015, Taxonomy and distribution of non-geniculate coralline red algae (Corallinales, Rhodophyta) on rocky reefs from Ilha Grande Bay, Brazil, Phytotaxa 192 (4), pp. 267-278 : 269-270

Lithophyllum corallinae (P.Crouan & H.Crouan) Heydrich, 1897: 47

( Figs. 2–5 )

Basionym:— Melobesia corallinae P.Crouan & H. Crouan, 1867: 150 , 252.

Lectotype:— P. L. Crouan & H. M. Crouan; CO ( Chamberlain 1991: 67).

Type locality:—Banc du Chateau et Baie de la Ninon, Rade de Brest, France ( Chamberlain 1991: 67).

Homotypic synonyms:— Dermatolithon corallinae (P.Crouan & H.Crouan) Foslie in Boergesen, 1902: 402; Tenarea corallinae (P.Crouan & H.Crouan) Notoya, 1974: 47 nom. inval.; Titanoderma corallinae (P.Crouan & H.Crouan) Woelkerling, Y.M.Chamberlain & P.C.Silva, 1985: 333 .

Heterotypic synonyms:— Lithophyllum macrocarpum f. corallinae (P.Crouan & H.Crouan) Foslie, 1909: 47 ; Lithophyllum pustulatum f. corallinae (P.Crouan & H.Crouan) Foslie, 1905: 118 , 227; Dermatolithon pustulatum var. corallinae Foslie ex Belsher et al. 1976: 51 comb.invl.

Material examined:— BRAZIL. Rio de Janeiro State, Comprida Island (22º57’45.45” S, 44º23’58.03” W, 29.x.2003, F. T. de S. Tâmega & M. A. de O. Figueiredo, RB 587132 ; RB 587133 ) .

central columella (C) and peripherally arranged, zonately divided tetrasporangia (te) (RB 587133). Scale bar = 50 μm.

Description:—Thalli non-geniculate, encrusting ( Fig. 2 ); 400–800 μm thick; internal construction dimerous ( Fig. 3 ) with a unistratose hypothallus composed of both palisade and non-palisade cells; single layer of rounded to elliptical epithelial cells ( Fig. 4 ) that measure 5–8 μm in length and 8–12 μm in diameter; subepithallial initials square to rectangular and measure 5–10 μm in length and 7–12 μm in diameter ( Fig. 4 ); perithallial cells square to rectangular and measure 10–18 μm in length and 5–11 μm in diameter; hypothallial cells square to elongate and measure 8–18 μm in length and 11–14 μm in diameter. Cells of adjacent perithallial and hypothallial filaments joined by secondary pit connections ( Fig. 4 ); cell fusions not observed.

Gametangial thalli were not observed. Mature tetrasporangial conceptacles uniporate and flush with, to raised above the surrounding thallus surface; conceptacle roofs 4–7 cells thick ( Fig. 5 ); conceptacle pore canal cells vertically arranged and do not project into the pore canal; conceptacle external diameter 125–400 μm; chambers 100–300 μm in diameter and 147–156 μm in height. A prominent central columella is present and zonately divided tetrasporangia that at maturity measure 45–57 μm in length and 23–32 μm in diameter, are located peripherally to it ( Fig. 5 ); conceptacle floor located 12–14 cells below the thallus surface ( Fig. 5 ).

Remarks:—Specimens ascribed to L. corallinae in this study show similarities in their tetrasporangial conceptacle characteristics with those previously reported for the species in the USA ( Taylor, 1960), Australia ( Woelkerling & Campbell 1992, Harvey et al. 2009), British Isles ( Irvine & Chamberlain 1994) and Brazil ( Villas-Boas et al. 2009, Amado-Filho et al. 2010, 2012), with only minor differences in the conceptacle roof thickness and the depth of the conceptacle floor ( Table 1).

Ecological observations:—The species is found in the mesolittoral zone below turf forming geniculate coralline algae at a depth of 0.5 m to the subtidal zone below Codium spongiosum Harvey (1.5 m depth) and Sargassum furcatum Kützing (4 m depth). Specimens were found without grazing scars, which may explain the presence of macroalgae and epiphytic bryozoans.

Geographical distribution:—The species has been widely reported from the Atlantic, Indian and Pacific oceans. See Guiry & Guiry (2014) for a detailed distribution list.

In Brazil the species has been reported from Espírito Santo ( Villas-Boas et al. 2009, Amado-Filho et al. 2010) and Fernando de Noronha Archipelago ( Amado-Filho et al. 2012).

Distribution within the study sites:—Comprida (22º57’45.45” S, 44º23’58.03” W) and Flechas (23º03’29.03” S, 44º20’18.52” W) islands.

Figures

FIGURES 2–5. Lithophyllum corallinae. FIGURE 2. External morphology (RB 587132). Scale bar = 1 cm. FIGURE 3. Longitudinal section showing dimerous thallus construction (white arrow) (RB 587133). Scale bar = 100 μm. FIGURE 4. Longitudinal section showing a single layer of rounded to elliptical epithallial cells (e), subepithallial initials (s) and secondary pit connections between adjacent filaments (white arrow) (RB 587133). Scale bar = 20 μm. FIGURE 5. Longitudinal section through a tetrasporangial conceptacle showing the