Zelometeorium patulum (Hedw.) Manuel

Authority

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

Family

Meteoriaceae

Scientific Name

Zelometeorium patulum (Hedw.) Manuel

Description

Species Description - Plants medium-sized but often in extensive, green to golden, pendent festoons. Stems pendent to creeping, to ca. 30 cm long, irregularly to regularly pinnate, the branches short, mostly <1 cm long, rarely the branch apices becoming flagellate; in cross-section with 3-5 rows of small thick-walled cells surrounding larger thin-walled cells, central strand small, of very small thin-walled cells; pseudoparaphyllia broadly foliose; axillary hairs with a single short-rectangular brown basal cell and 2-3 elongate hyaline distal cells. Stem and branch leaves differentiated, inserted in a U-shaped line, stem leaves erect to erect-spreading from a clasping base, narrowly to broadly ovate, ca. 2 mm long, abruptly acuminate, the acumen flexuose and often piliferous, broadly auriculate, the auricles ca. 30-40% of the leaf base (excluding the acumen); margins subentire to serrulate throughout, plane throughout; costa single, slender, ending near midleaf, sometimes barely above the auricles or rarely almost to base of the acumen; cells linear, smooth, with thickened endwalls but otherwise thin- to firm-walled, usually not or scarcely porose but becoming obviously so toward the insertion; alar cells scarcely differentiated to fairly obvious in small, excavate groups, subquadrate to short-rectangular, firm- to thick-walled, somewhat porose. Branch leaves densely disposed, wide-spreading to squarrose-recurved, sometimes somewhat contorted when dry, mostly ovate, 0.85-2.2 mm long (the longer ones more acuminate), short- to long-acuminate, sometimes piliferous, the base mostly cordate, slightly clasping; margins subentire, denticulate or serrulate throughout, plane throughout or narrowly recurved near insertion; costa single, slender, ending near midleaf or to ca. 3/4 the leaf length (excluding the acumen) and then often projecting as a small prickle; cells fusiform to linear-flexuose, smooth, firm-walled, sometimes ± porose, becoming rectangular and porose toward the insertion; alar cells indistinct to obvious in small, well marked groups, subquadrate, firm-to thick-walled, sometimes slightly porose. Asexual propagula rarely present, of flagellate branches. Dioicous. [Sporophytes not seen from the West Indies; description based on South American material.] Perichaetial leaves loosely erect with erect-spreading apices, oblong-lanceolate, 2.2-2.9 mm long, abruptly long-acuminate, concave; margins serrulate in the acumen, subentire below, plane; costa single, extending to base of the acumen; cells linear, smooth, thick-walled, porose. Setae relatively short, slightly roughened, reddish, ca. 3 mm long, straight or curved; capsules short-exserted, erect, long-cylindric, 2-4 mm long; exothecial cells rectangular, with thick vertical walls and thinner horizontal walls, becoming subquadrate toward the mouth; annulus of 2 rows of thick-walled subquadrate cells; operculum conic-rostrate, the rostrum straight, 1-1.5 mm long; peristome inserted ca. 100 µm below the mouth, exostome teeth linear-triangular, yellow, scarcely bordered, on the front surface with a straight median line, sparsely papillose below, densely papillose-spiculose above, not trabeculate at back, unomamented; endostome with a low basal membrane emergent from capsule mouth, smooth to sparsely papillose, segments papillose-spiculose, keeled, perforate, ca. as long as the teeth, cilia rudimentary. Spores spherical, bluntly low-papillose, 14-23 µm diam. Calyptrae mitrate, lobed at base, erect-pilose, the hairs 1-3(-4)-seriate, roughened above.

Discussion

1. Zelometeorium patulum (Hedw.) Manuel, J. Hattori Bot. Lab. 43: 118. 1977; Hypnum patulum Hedw., Sp. Musc. Frond. 279. 1801; Neckera patula (Hedw.) Schwagr., Sp. Muse. Frond. Suppl. 2(2): 43. 1823; Pilotrichum patulum (Hedw.) Brid., Bryol. Univ. 2: 759. 1827; Meteorium patulum (Hedw.) Dozy & Molk., Prodr. Fl. Bryol Surinam. [Natuurk. Verh. Holl. Maatsch. Wetensch. Haarlem II, 10(3):] 21. 1854; lsothecium patulum (Hedw.) Mont, ex Dozy & Molk., Prodr. Fl. Bryol. Surinam. [Natuurk. Verh. Holl. Maatsch. Wetensch. Haarlem II, 10(3):] 21. 1854; Meteoriopsis patula (Hedw.) Broth, in Engl. & Prantl, Nat. Pflanzenfam. 1(3): 825. 1906. Plate 99, figures 10-18 Pilotrichum recurvifolium Hornsch. in Mart., Fl. Bras. 1(2): 58. 1840; Meteorium recurvifolium (Hornsch.) Mitt., J. Linn. Soc., Bot. 12: 444. 1869; Meteoriopsis recurvifolia (Hornsch.) Broth, in Engl. & Prantl, Nat. Pflanzenfam. 1(3): 825. 1906; Zelometeorium recurvifolium (Hornsch.) Manuel, J. Hattori Bot. Lab. 43: 121. 1977. Meteorium stellatum Lorentz, Moosstudien 165. 1864; Meteoriopsis stellata (Lorentz) Broth, in Engl. & Prantl, Nat. Pflanzenfam. 1(3): 826. 1906.\ Discussion. Zelometeorium patulum is characterized by its frequently pendent habit, clasping, long-acuminate stem leaves, and densely disposed, spreading to squarrose-recurved branch leaves. It has been confused with Meteoridium remotifolium, which has leaves much further apart on the stems and branches, spreading from the insertion, more strongly serrate, often with twisted apices, and alar cells more elongate, thick-walled and more noticeably porose. There are also sporophytic differences, but since neither species is usually found fertile, they are of little aid in identification. In his monograph of Zelometeorium, Manuel (1977b) reported a single collection of Z. recurvifolium from the West Indies. However, he annotated a duplicate of that collection as Z. patulum. Actually, about half of all West Indian collections fall within the variation assigned to Z. recurvifolium. After careful study, I think the two taxa are nothing more than growth forms. Within the species, branch leaves range from short-acuminate to piliferous, with all possible intermediates. Leaf margins vary from subentire to sharply serrulate, and the costa may extend almost to the base of the acumen (and then often—but not always—end in a small spine) or may be short and end below midleaf. Alar cells may be scarcely differentiated to obvious in excavate groups. Unfortunately, none of these characters correlates with any other one. Leaves with short apices sometimes have less-toothed margins and shorter costae, but not often enough to offer definition to a segregate taxon. According to both Manuel (1977b) and a note by A. L. Andrews in hb. NY, both extremes are among Swartz’s original gathering of the species from Jamaica. Oddly, Manuel did not register Z. recurvifolium from Jamaica even though he cited half of the material in Hedwig’s herbarium in Geneva as that species.

Distribution

Range. Florida, Mexico, Central America, northern South America (south to northern Chile, Bolivia and southeastern Brazil); Cuba, Jamaica, Hispaniola (Haiti and Dominican Republic), Puerto Rico, Saba, St. Eustatius, St. Kitts, Nevis, Montserrat, Guadeloupe, Dominica, Martinique, St. Vincent; growing on tree trunks and rocks, and pendent from branches and leaves, in humid forests, from near sea level to ca. 1500 m (higher in South America).

United States of America North America| Mexico North America| Central America| Chile South America| Bolivia South America| Brazil South America| Peru South America| Ecuador South America| Colombia South America| Venezuela South America| Guyana South America| Suriname South America| French Guiana South America|