BFNA Title: Schlotheimia
7. SchlotheimIA Bridel, Musc. Recent. Suppl. 2: 16. 1812 * [For Ernst Friedrich von Schlotheim (1764--1832), a paleontologist held in high regard by Bridel]
Dale H. Vitt
Plants medium-sized, in dense, tomentose, usually reddish-brown mats on trees. Stems creeping, with numerous, ascending, stout, usually forked branches up to 2 cm high. Branch leaves appressed to loosely-appressed, erect, often spirally-twisted around stem when dry, narrowly lanceolate to oblong-ligulate, usually acute, apiculate or long-cuspidate, sometimes rugose; margins entire; costa strong, excurrent or ending at apex; distal laminal cells small, rarely greater than 10 µm, rounded, thick-walled, usually smooth; basal laminal cells elongate, porose. Sexual condition pseudautoicous, dwarf male plants on leaves of female plant. Seta smooth. Capsule fully exserted, rarely immersed; elliptic to cylindric, erect, usually smooth or lightly plicate; stomates superficial; peristome double; endostome segments 16, shorter than exostome, pale sometimes rudimentary; exostome teeth 16, well-developed, linear-lanceolate, often blunt, erect or recurved, thick densely papillose-striate. Calyptra mitrate, long-conic to campanulate, 4--6 lobed at base, naked or hairy, usually covering entire capsule. Spores anisosmorphic.
Species 100--150 (2 in the flora); pantropical; Mexico, Central America, South America, Africa, Australia, Pacific Islands (New Zealand).
The distinctive dark-reddish coloration, habit in tree canopies and on tree trunks, and 4--6 lobed, campanulate calyptra are diagnostic features of this genus.
1. Leaves gradually acute or acuminate, not rugose; calyptrae smooth.............. . . . . Schlotheimia lancifolia
1. Leaves abruptly apiculate, rugose; calyptra papillose near apex . . . . Schlotheimia rugifolia
1. Schlotheimia lancifolia E. B. Bartram, Bryologist 35: 9. 1932
Plants in shiny, bright-green, reddish-brown, or dark-brown mats. Stems up to 16 mm. Stem leaves oblong lanceolate to narrowly-lanceolate, 1.5--2.3 mm, gradually narrowed to narrowly acute or acuminate, sometimes serrulate apex, not rugose or undulate; costa percurrent; distal laminal cells 6--8 µm wide, irregularly quadrate to rounded-elliptic. Seta 3--5 mm. Capsule 1.4--2 mm.
Logs, trunks of trees to 8 m; extremely rare and probably restricted to undisturbed hemlock-hardwood zone; moderate elevations; endemic to southern Blue Ridge Escarpment; N.C.
This species differs from S. rugifolia in having non-rugose, gradually acute leaves.
2. Schlotheimia rugifolia (Hooker) Schwaegrichen, Spec. Musc. Suppl. 2(1): 150. 139. 1824
Orthotrichum rugifolium Hooker, Musci Exot. 2: 19. 128. 1819
Plants in reddish-brown to dark-brown mats. Stems 2--8 mm. Stem leaves oblong to oblong-ligulate, 1.4--1.6 mm, mucronate to apiculate, rugose; costa shortly excurrent into mucro; distal laminal cells 5--9 µm wide, rounded-quadrate. Seta 2.5--4 mm. Capsule 1.7--2.2 mm.
Logs, trunks of trees frequently above 3 m, often on branches in tree canopies; low elevations; Ala., Fla., Ga., La., Miss., N.C., S.C., Tenn., Texas, Va.; Mexico; West Indies; Central America; South America.
Schlotheimia rugifolia is distinguished by rugose, abruptly apiculate leaves. Characteristically the plants have a dark reddish-brown color, which is best developed under xeric conditions.