Pleonosporium globuliferum Levring 1941: 647

Mateo-Cid, Luz Elena, Mendoza-González, A. Catalina, Norris, James N. & García-López, Deisy Y., 2018, A taxonomic account of species in the tribe Spongoclonieae (Ceramiaceae, Ceramiales, Rhodophyta) reported from Atlantic and Pacific Mexico, Phytotaxa 340 (3), pp. 229-245 : 232

Pleonosporium globuliferum Levring 1941: 647 ( Figs. 9–14 )

Type locality: Quebrada Sánchez (Ausserhalb Sanchez), Isla Alejandro Selkirk ( Isla Más Afuera ; Masafuera ), Islas Juan Fernández , Valparaíso Región, Chile .

Distribution. EASTERN PACIFIC: Gulf of California, México (Sonora, and Baja California Sur); Pacific México: Baja California ( Isla Guadalupe), Jalisco, Colima, and Oaxaca; El Salvador; Costa Rica; and Chile ( Dawson, 1961, 1962a, 1962b; Mateo-Cid et al., 2000; Bucher and Norris, 2014; Norris et al., 2017; herein). WESTERN PACIFIC: South China Sea, and Philippines ( Silva et al., 1987; Phang et al., 2016).

Specimens studied. GULF OF CALIFORNIA. Baja California Sur: Punta Arenas (109°48’17”W, 23°59’51”N), coll. Mateo-Cid & Mendoza-González, 26-04-1994 ( ENCB 12386 ; ♀, polysporangia). PACIFIC MÉXICO. Jalisco: Chamela (105°05’00”W, 19°31’45”N), coll. Mateo-Cid & Galicia García, 06-10-1991 ( ENCB 18859 ; ♀, ♂) ; Colima: Manzanillo (104°20’51”W, 19°06’18”N), coll. Mendoza-González & Mateo-Cid, 14-12-1985 ( ENCB 8267 ; polysporangia) ; and, Oaxaca: Salina Cruz (95°12’11”W, 16°09’37”N), coll. Mateo-Cid & Mendoza-González, 08-08- 1992 ( ENCB 14958 ; ♂, ♀, polysporangia) .

Habitat. On rocks, and epiphytic on species of Codium and Sargassum , or sometimes entangled with other algae; intertidal to shallow subtidal; on rocks, tidal platforms, and in tidal pools.

Morphology, Anatomy and Reproductive structures. Thalli tufted, of several erect, axes multifariously branched throughout, up to 2 cm tall, rosy; primary axes ecorticate; ultimate branchlets alternately divided, upcurved, with blunt apical cell; attached by a group of branched, multicellular, penetrating rhizoids. Cells of main filaments 140–150 μm in diameter and 120–200 μm long; middle cells 70–80 μm in diameter and 100–120 μm long; determinate lateral branches 1 mm long or more, ascending and mostly curved, about 26–30 μm in diameter, 30–60 μm long, with blunt apices.

Polysporangia sessile, subspherical, (25–) 40–90 (–100) μm in diameter (including thick hyaline cell wall); divided into thirty-two spores; scattered along lateral branches, mainly adaxial. Gametangial thalli dioecious. Spermatangial clusters subcylindrical, 70–80 μm long, 30–40 μm in diameter; sessile along adaxial side of lateral branchlets. Cystocarps subspherical, 450–500 μm in diameter; developed in the terminal portions of thallus.

Remarks. Although our SW Gulf of California and Pacific Mexico specimens are mostly in agreement with descriptions of Dawson (1962a) and Bucher and Norris (2014), they are taller and the cells of the main axes are larger.

Figures

FIGURES 9–16. Species of Pleonosporium: Pleonosporium globuliferum, Salina Cruz, Oaxaca (ENCB 14958). 9) Habit, female gametophyte. Scale bar: 9 mm. 10) Ecorticate axis with determinate lateral branches. Scale bar: 150 μm. 11) Detail of upper portions showing strongly curved ultimate branchlets. Scale bar: 150 μm. 12) Branch of sporophyte with polysporangia (arrows) sessile. Scale bar: 75 μm. 13) Spermatangial cluster (arrow). Scale bar: 45 μm. 14) Mature carposporophyte (bracket) with carposporangia (arrows). Scale bar: 230 μm. Pleonosporium mexicanum, Santa Elena Cozoaltepec, Oaxaca (ENCB 14964). 15) Habit of male gametophyte. Scale bar: 9 mm. 16) Basal portion of thallus showing rhizoidal attachment. Scale bar: 450 μm.