Sphagnum recurvum P.Beauv.
-
Authority
Sharp, Aaron J., et al. 1994. The Moss Flora of Mexico. Part One: Sphagnales to Bryales. Mem. New York Bot. Gard. 69 (1): 1-452.
-
Family
Sphagnaceae
-
Scientific Name
-
Description
Species Description - Plants moderately robust, in bright-green to yellow-brown carpets. Capitulum often conspicuously 5-radiate; young pendent branches as seen between the arms of the capitulum paired; leaves of young spreading branches spiral-ranked when moist; tip of stem and base of spreading branches often pink-flushed. W o o d cylinder of stem yellow-green; cortical cells poorly differentiated in 1 layer, long-rectangular, without fibrils or pores. Stem leaves flat, 0.7-1.3 mm long, usually somewhat longer than broad, ± Ungulate or less commonly broadly triangular, moderately erose across a broadly rounded or tmncate, flat apex, the border of linear cells broader at base but not abruptly widened or sharply differentiated; hyaline cells not divided, without pores or fibrils (or rarely ± fibrillose above), mostly resorbed on the inner surface toward the apex. Branches in fascicles of 5 (with 2-3 spreading); cortical cells without fibrils, the retort cells with inconspicuous necks. Branch leaves ± flattened, recurved at tips, and wavy at margins when dry, lanceolate, involute-concave, and erect with incurved margins when moist, 1.3-1.4 mm long, bordered by 2-4 rows of linear cells, entire except across the narrow, tmncate apex; hyaline cells fibrillose, nearly plane on the outer surface, slightly convex on the inner, on the outer surface with a moderately large and rather conspicuous round pore at the upper end and near the apex of the leaf with a few small, ringed pores in corners and along commissures, on the inner surface with 3-7 rather large, round, unringed pores at corners and near commissures (usually evident only on strong staining); green cells in section isosceles-triangular, with the base exposed on the outer surface, the apex of the triangle usually reaching the inner surface. Dioicous. Spores 24-27 µm, finely roughened to nearly smooth.
-
Discussion
Fig. 8
recurvum P.-Beauv., Prodr. Aetheog. 88. 1805.
S. pulchricoma C. Mull., Syn. Muse. Frond. 1: 102. 1848.
Sphagnum recurvum develops yellow to yellow-brown tinges in the sun, but shade forms can be bright-green. The capitulum is often conspicuously 5-radiate, and between the rays the young pendent branches appear to be paired. A pink flush is common at the base of spreading branches and near the tip of the stem. The stem leaves are broadly lingulate and somewhat erose at a broad, tmncate or more or less rounded apex. The branch leaves, at least on young spreading branches of the capitulum, are noticeably spiral-seriate when moist. O n drying the branch leaves are relatively flat, with spreading or recurved tips and wavy margins. The hyaline cells of branch leaves have few pores on the outer surface, but a rounded pore at the upper end of each cell is rather conspicuously windowlike (seeming to be a perforated through both outer and inner surfaces); on the inner surface are numerous rounded pores with thin margins, especially noticeable on strong staining.
Sphagnum sancto-josephense Crum & Crosby, of Costa Rica and northern South America, has oblong, concave-acute stem leaves with hyaline cells fibrillose on the outer surface toward the apex; the inner surface is largely resorbed, but mere stumps of fibrils m a y be seen fringing the uppermost cells.
Sphagnum cuspidatum Ehrh. ex Hoffm. var. serrulatum (Schlieph.) Schlieph. (5. trinitense C. Miill.), widely distributed in coastal regions of eastern North America and in the West Indies and northern South America, has been found in Honduras and Costa Rica. An aquatic, it has leaves somewhat flattened and wavy when dry. The branch leaves are long and narrow, and at the branch tips they are especially long-subulate and, when dry, loosely flexuose; the margins (especially in elongate leaves at branch tips) are serrulate toward the apex and sometimes well below it. The variety is, in most of its structural features, much like the var. cuspidatum, but it is rather more robust and tends to have hyaline cells of stem leaves once-divided. The var. cuspidatum has been found in Costa Rica and the Galapagos.
Sphagnum macrophyllum Brid., a species of coastal distribution in eastern North America occurring disjunctively in Honduras, can be expected in the Mexican lowlands. The plants grow in shallow water, often floating just below the surface The long, narrow leaves are crowded together on short bristly branches. Their long, narrow hyaline cells are similar in shape and size to the green cells, but they have as many as 20 large, round pores in a median row on the outer surface The var. floridanum Aust., of similar distribution northward, has hyaline cells perforated by as many as 60 small pores in two rows.
-
Distribution
In relatively base-rich depressions in open or shaded peatlands; Veracruz (Huayacocotla).—Eastern Mexico; eastern North America; Cuba; Brazil; northern South America; southeastern Asia and the Malaysian Archipelago, Taiwan, and the Philippines; Madagascar.
Madagascar Africa| Philippines Asia| Taiwan Asia| Malaysia Asia| Asia| French Guiana South America| Suriname South America| Guyana South America| Venezuela South America| Colombia South America| Ecuador South America| Peru South America| Brazil South America| Bolivia South America| Cuba South America| North America| Mexico North America|