Isodrepanium lentulum (Wilson) E.Britton

  • Authority

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

  • Family

    Neckeraceae

  • Scientific Name

    Isodrepanium lentulum (Wilson) E.Britton

  • Description

    Species Description - Plants medium-sized to somewhat robust, in very lustrous, pale-green to dark-golden, flat, often dense, scrambling mats. Primary stems creeping, occasionally pendent, to ca. 30 cm long, but rarely >10 cm, irregularly 1-2-pinnate, the branches elongate, occasionally becoming flagellate, strongly complanate-foliate; in cross-section with 3-4(-5) rows of small thick-walled cells surrounding larger thin- to firm-walled cells, central strand none; paraphyllia none; pseudoparaphyllia foliose; axillary hairs with (1-) 2(-3) short brown basal cells and (2-)3-5 elongate hyaline distal cells. Stem and primary branch leaves similar, those of secondary branches often much smaller and relatively narrower, strongly complanate, spreading to wide-spreading, cultriform to sigmoid-oblong, strongly asymmetric, 1.5-2.5 mm long, short-acuminate, apex often recurved when dry, sometimes ± undulate, not decurrent but ± rounded to the insertion, often caducous and leaving naked areas on stems and branches; margins serrulate in upper ½, subentire below, inflexed below on concave margin; costa short and double; cells long-hexagonal to linear-subflexuose, ca. 8-12:1, smooth, firm-walled, porose, becoming somewhat shorter in the acumen, becoming slightly longer and more strongly thick-walled and porose toward the ± yellowed insertion; alar cells not differentiated. Asexual propagula none. Dioicous. [Rarely fertile; description based on a Guatemalan specimen.] Perichaetial leaves convolute, oblong, 2-2.7 mm long, abruptly long-acuminate, the acumen as long as or longer than the base; margins serrulate at extreme apex and on shoulders, subentire elsewhere, plane; costa ± single, ending well below the base of the acumen, sometimes double; cells linear, smooth, very thick-walled and porose, becoming shorter and broader toward the insertion. Setae very long, smooth, reddish, 4-5 cm long; capsules suberect to horizontal, broadly short-cylindric, 1.5-2.1 mm long; exothecial cells short-rectangular, thick-walled, becoming shorter in ca. 2 rows at mouth; annulus not seen but probably not differentiated; operculum not seen; peristome deeply inserted, exostome teeth on the front surface densely cross-striolate below, coarsely papillose above, moderately trabeculate at back; endostome with a high basal membrane, segments finely and sparsely papillose, keeled, perforate, ca. as long as the teeth, cilia seemingly in pairs (broken). Spores spherical, finely papillose, 14-21 µm diam. Calyptrae not known.

  • Discussion

    1. Isodrepanium lentulum (Wilson) E. Britton in E. Britton & R. S. Williams, Torreya 14: 28. 1914; Homalia lentula Wilson, Ann. Mag. Nat. Hist. 20: 379. 1847, “Ornaba’; Neckera lentula (Wilson) Broth, in Engl. & Prantl, Nat. Pflanzenfam. 1(3): 842. 1906. Plate 41, figures 1-9 Hookeria membranacea Miill. Hal., Syn. Musc. Frond. 2: 200. 1851; Lepidopilum membranaceum (Miill. Hal.) Mitt., J. Linn. Soc., Bot. 12: 369. 1869; Homalia membranácea (Miill. Hal.) Müll. Hal., Hedwigia 37: 266. 1898. Neckera falcifolia Renauld & Cardot, Bull. Soc. Roy. Bot. Belgique 32(1): 184. 1893. Discussion. Isodrepanium lentulum is characterized by strongly complanate and asymmetric. ± falcate-cultriform leaves. The laminal cells are firm-walled and porose, with virtually no alar differentiation. The costa is short and double or absent. The species might only be confused with mosses not at all related, such as Lepidopilum scabrisetum and its relatives. In this group of Lepidopilum the aspect, leaf shape, and lack of a costa are similar; however, the laminal cells are all lax, thin-walled, and not at all porose.

  • Distribution

    Range. Mexico to Panama, Colombia, Venezuela, Ecuador, Surinam, French Guiana, Trinidad; Cuba, Jamaica, Hispaniola (Haiti and Dominican Republic), Puerto Rico, Guadeloupe, Dominica. Martinique, St. Vincent, Barbados; growing on twigs and slender tree trunks, less often on soil or rock, in moist to cloud forests, at 600-1300(-1800) m.

    Mexico North America| Central America| Colombia South America| Venezuela South America| Ecuador South America| Suriname South America| French Guiana South America| Trinidad and Tobago South America| Cuba South America| Jamaica South America| Haiti South America| Dominican Republic South America| Puerto Rico South America| Guadeloupe South America| Dominica South America| Martinique South America| Saint Vincent and the Grenadines South America| Barbados South America|