Spatoglossum lanceolatum E. Y. Dawson 1954

Spatoglossum lanceolatum E. Y. Dawson

Spatoglossum lanceolatum E. Y. Dawson, 1954e:328, pl. 1: figs. 1, 2, pl. 6; Dawson, 1961b:389; González-González et al., 1996:164; Pedroche et al., 2008:56.

Algae of few to several flat, 3–4 times irregularly, subdichotomously to subpalmately divided fronds, up to 28 cm tall, above a narrow slightly stupose stipe, up to 10 mm long and 1.0–2.0 mm wide; attached below by a discoid stupose cushion. Branches narrower near dichotomies, widening upward, becoming more or less lanceolate, to (3–)5–10(–17) mm broad; margins with irregularly spaced dentations; blades 200–250 µm thick. Medulla of (3–)5–7 irregular layers of large cells, 40–65 µm in diameter; subcortex of partial layers of similarly shaped smaller cells. Cortex of quadrangular cells, not projecting, outer walls forming a smooth surface; in surface view, cells of irregular shape and irregularly arranged (not in longitudinal rows).

Apparently monoecious. Oogonia ovate to hemispherical (or sometimes more or less angular), up to about 70 µm in diameter; either solitary, in pairs, or in groups of 3–4; embedded within cortical layer (barely projecting above its suface). Antheridia in sori, 100–200 µm in diameter, embedded in cortical layer and not projecting above surface; composed of densely packed cells, most 8–9 µm in diameter; formed by periclinal cell divisions into irregular tiers within vertical columns, 30–40 µm tall.

HABITAT. On rocks, in tide pools, and on tidal platforms; mid intertidal to shallow subtidal.

DISTRIBUTION. Gulf of California: Puerto Peñasco to Ensenada de San Francisco.

TYPE LOCALITY. North shore of Ensenada de San Francisco, near Punta de Las Cuevas, Sonora, Gulf of California.