Phyllodon truncatulus (Müll.Hal.) W.R.Buck

  • Authority

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

  • Family

    Hypnaceae

  • Scientific Name

    Phyllodon truncatulus (Müll.Hal.) W.R.Buck

  • Description

    Species Description - Plants somewhat small, in dull, ± stiff, green to yellow-green, flat mats. Stems creeping, elongate, to ca. 3 cm, subpinnately branched, the branches numerous, elongate, complanate-foliate; in cross-section with 2-3 rows of small thick-walled cells surrounding abruptly larger thin-walled cells, central strand of small very thin-walled cells; pseudoparaphyllia foliose; axillary hairs with a single short brown basal cell and 2 elongate hyaline distal cells. Stem and branch leaves similar but dorsal and ventral leaves differentiated from lateral leaves, complanate, erect- to wide-spreading, often asymmetric, broadly ligulate, 0.75-1 mm long, dorsal and ventral leaves narrower than lateral leaves, broadly rounded to emarginate, lateral leaves very concave; margins sharply serrate above, the teeth bifid, serrulate below, plane; costa short and double or absent; cells linear-flexuose, prorulose and seriately papillose, the papillae lower in basal 1/2 of leaf, thin-walled; alar cells scarcely differentiated, with a few subquadrate, concolorous cells in basal angles and across the insertion. Asexual propagula none. Synoicous. Perichaetial leaves ovate to oblong-ovate, 0.61.25 mm long, obtuse to short-acuminate; margins singly to doubly serrate above, entire below, plane; costa none; cells linear-flexuose, spiculose, the "papillae" to 30 pm tall, thick-walled, shorter and smooth toward the insertion; alar cells not differentiated. Setae elongate, smooth, reddish, 1.5-2.5 cm long; capsules inclined, arcuate, asymmetric, ovoid, ca. 1.25 mm long; exothecial cells oval to short-rectangular, firm-walled, not collenchymatous; annulus of 1-2 rows of thick-walled cells; operculum high-conic, ca. 0.8 mm long; exostome teeth yellow-brown, shouldered, bordered, on the front surface cross-striolate below, coarsely papillose above, trabeculate at back; endostome yellowish, with a high, smooth basal membrane, segments finely papillose, keeled, perforate, ca. as long as the teeth, cilia finely papillose, single, broad, 2-3-seriate below, sometimes split in two above. Spores spherical, finely papillose, 13-17 µm. Calyptrae cucullate, naked, smooth, falling early.

  • Discussion

    1. Phyllodon truncatulus (Müll. Hal.) W. R. Buck, Mem. New York Bot. Gard. 45: 521. 1987; Hypnum truncatulum Müll. Hal., Syn. Musc. Frond. 2: 263. 1851; Ectropothecium truncatulum (Müll. Hal.) Mitt., J. Linn. Soc., Bot. 12: 517. 1869; Trichosteleum truncatulum (Müll. Hal.) A. Jaeger, Ber. Thätigk. St. Gallischen Naturwiss. Ges. 1876-77: 415. 1878; Glossadelphus truncatulus (Müll. Hal.) M. Fleisch., Musci Buitenzorg 4: 1352. 1923. Plate 129, figures 1-7 Hookeriopsis cocoensis R. S. Williams, Bryologist 27: 40. 1924; Glossadelphus cocoensis (R. S. Williams) E. B. Bartram, Proc. Calif. Acad. Sci. IV, 21: 86. 1933. Glossadelphus longisetus E. B. Bartram, Contr. U.S. Natl. Herb. 26(3): 109. 1928. Discussion. Phyllodon truncatulus is an extraordinary species not likely to be confused with any other due to the ligulate leaves with broadly rounded apices and strongly prorulose and papillose cells. The marginal bifid serrations are particularly striking. The species seems close to the Angolan P. truncatus (Welw. & Duby) W. R. Buck but differs, among other features, by the smooth rather than strongly roughened seta.

  • Distribution

    Range. Costa Rica, Panama, Colombia, Ecuador, Peru, Brazil, French Guiana; Jamaica, Hispaniola (Haiti and Dominican Republic), Puerto Rico, St. Vincent; growing mostly on moist rocks, but also on tree trunks, in humid forests, at 200-600(-1200) m.

    Costa Rica South America| Panama Central America| Colombia South America| Ecuador South America| Peru South America| Brazil South America| French Guiana South America| Jamaica South America| Dominican Republic South America| Haiti South America| Puerto Rico South America| Saint Vincent and the Grenadines South America|