Thuidium tamariscinum (Hedw.) Schimp.

Authority

Buck, William R. 1998. Pleurocarpous mosses of the West Indies. Mem. New York Bot. Gard. 82: 1-400.

Family

Thuidiaceae

Scientific Name

Thuidium tamariscinum (Hedw.) Schimp.

Description

Species Description - Plants robust, in often large, often dense, yellow-green, green, or golden mats. Stems mostly ± arched, to ca. 15 cm long, 2-3-pinnate, ± frondose; in cross-section with 3-5 rows of small thick-walled dark-red cells surrounding larger thinner-walled cells, central strand small, of small cells; paraphyllia very abundant on stems and primary branches, few or none on secondary and tertiary branches, polymorphous, mostly uniseriate but branched, some foliose with uniseriate filaments, the cells rectangular, ca. 2-4: 1, usually with 1-2 papillae/cell and not restricted to cell ends; pseudoparaphyllia foliose; axillary hairs with a single short brown basal cell and 2 elongate hyaline distal cells. Stem and branch leaves strongly differentiated, stem leaves appressed when dry, erect-spreading when moist, triangular-ovate, 0.9-1.7 mm long, gradually or ± abruptly and broadly acuminate, concave, plicate, shortly and narrowly decurrent; margins papillose-serrulate throughout, irregularly recurved from base of acumen to insertion; costa single, strong, ending 4/5 the leaf length to subpercurrent, not filling the acumen, papillose, sometimes with a few short paraphyllia near base; cells oval, subquadrate or ± short-rectangular, unipapillose with the papillae centrally located over the lumina, stout, straight or slightly curved, supracostal cells smooth; alar cells not differentiated but cells across the insertion rectangular, thick-walled, porose, and smooth in 2-4 rows, cells of the decurrencies subquadrate. Secondary and tertiary branch leaves erect when dry, spreading when moist, lanceolate-ovate to ovate, 0.4-0.8 mm long, acute to short-acuminate, concave, not plicate, not decurrent; margins papillose-serrulate, plane; costa single, ending 1/2-2/3 the leaf length, often forked above; cells ± oval, ca. 8 µm wide, stoutly unipapillose with the papillae curved, often ± angular, thick-walled, ± porose, the apical cell ± elongate, pointed, smooth as the 1-2(-3) tiers of cells below it; alar cells not differentiated. Asexual propagula none. Dioicous. [Sporophytes not known in the West Indies; description based on Swedish material.] Perichaetial leaves mostly erect, long-loriform from an oblong base, 3.5(-6) mm long, concave; margins serrulate above, densely ciliate on shoulders, the cilia uniseriate, plane; costa single, ending well into but not filling the acumen; cells long-hexagonal to long-rectangular, often unipapillose, firm-walled, not porose. Setae elongate, stout, smooth, reddish, 2.5-3.5 cm long; capsules horizontal, asymmetric and arcuate, cylindric, 2-4 mm long; ex-othecial cells ± short-rectangular, very thick-walled; annulus differentiated; operculum obliquely conic-rostrate; exostome teeth yellow to yellow-brown, shouldered, bordered, on the front surface cross-striolate below, then finely papillose, then coarsely papillose at apex, trabeculate at back; endostome with a high, smooth basal membrane, segments finely papillose, keeled, not or very narrowly perforate, cilia finely papillose, in groups of 2-3, nodulose. Spores spherical, finely roughened, ca. 18 µm diam. Calyptrae not seen.

Discussion

1. Thuidium tamariscinum (Hedw.) Bruch & Schimp. in Bruch, Schimp. & W. Gümbel, Bryol. Eur. 5(fasc. 49/ 51, Monogr. 1): 163. 1852; Hypnum tamariscinum Hedw., Sp. Musc. Frond. 261. 1801; Leskea tamariscina (Hedw.) Mitt., J. Linn. Soc., Bot. 8: 8. 1865, hom, illeg., non Hedw., Sp. Musc. Frond. 212. 1801 [= Canalohypopterygium tamariscinum (Hedw.) Kruijer]; Thuidium tamariscifolium Lindb., Not. Sallsk. Fauna Fl. Fenn. Förh. 13: 415. 1874, nom. inval. Plate 72, figures 1-10 Discussion. Thuidium tamariscinum is related to T. delicatulum and they are the only members of Thuidium in the West Indies with long-celled paraphyllia. Thuidium tamariscinum is distinct, though, in the apical cells of branch leaves pointed and smooth.

Distribution

Range. Newfoundland, Europe, Japan; Jamaica, known from a single collection (Nichols 27, NY) made at Cinchona on a moist, grassy place behind old greenhouses on 26 Aug 1906. It has not been collected since and was surely an accidental and unsuccessful introduction.

Canada North America| Europe| Japan Asia| Jamaica South America|