BFNA Title: Meteoriaceae
Author: W. D. Reese
Date: February 13, 2008
Edit Level: R
Version: 3

Bryophyte Flora of North America, Provisional Publication


Return to Home


William D. Reese†

Plants medium-sized to large, dull or glossy, with creeping primary stems bearing spreading or pendent branches, dark- to light-green or yellowish to brownish or blackish. Stems subpinnate to very irregularly branched, paraphyllia lacking, pseudoparaphyllia foliose. Branches short to elongate, simple to much-branched. Stem and branch leaves similar, spirally inserted, imbricate to spreading or squarrose, mostly broadly to narrowly acuminate, margins mostly serrate, apex acute to acuminate or piliferous; costa single or lacking; medial cells elongate, mostly papillose; alar cells sometimes differentiated. Sexual condition mostly dioicous, occasionally autoicous. Perigonia gemmiform, axillary. Perichaetia gemmiform, axillary. Seta single, short, dark. Capsule mostly exserted, mostly erect and symmetric, stomates proximal; annulus mostly indistinct; operculum conic-rostrate; peristome double, exostome of 16 teeth; endostome of 16 segments on a basal membrane, cilia lacking or inconspicuous. Calyptra cucullate or conic-mitrate, smooth or hairy. Spores spherical, smooth or rough.


Genera ca. 30, species ca. 260 (3 genera, 3 species in the flora): worldwide, primarily tropical and subtropical regions.


The Meteoriaceae is a large and diverse family with plants characteristically found on twigs and bark in warm humid regions of the world. Many of the taxa grow as tangled festoons of delicate branches dangling from the substrate. The twig habitat, creeping stems with pendent branches, elongate mostly papillose leaf cells, and pointed leaves often with uniseriate filiform apices evoke the image of the family. The taxonomy and phylogenetic relationships of this complex group of mosses are difficult to interpret. See W. R. Buck (1994) for proposals on generic concepts in Meteoriaceae.


SELECTED REFERENCES  Buck, W. R. 1994. A new attempt at understanding the Meteoriaceae. J. Hattori Bot.Lab. 75: 51--72. Noguchi, A. 1976. A taxonomic revision of the family Meteoriaceae of Asia. J. Hattori Bot. Lab. 41: 231--357.


1. Leaf cells smooth      3. Zelometeorium, p. xx

1. Leaf cells papillose.

2. Stems and branches densely foliate; leaf cells in rows diverging from costa     1. Papillaria, p. xx.

2. Stems and branches loosely foliate; leaf cells not evidently in rows diverging from costa          2. Barbella, p. xx


1. PAPILLARIA (Müller Hal.) Müller Hal. ex Ångström, name conserved, Oefvers. Förh. Kongl. Svenska Vetensk.-Akad. 33(4): 34. 1876 *  [Latin papula, a nipple, alluding to the papillae on the leaf cells]


Neckera subsect. Papillaria Müller Hal., Syn. Musc. 2: 134. 1850


Plants medium-sized, dull, with short erect or elongate terete pendent branches, green to yellowish green or brownish. Primary stems irregularly to subpinnately branched, axillary hairs with 1--2 short, brownish proximal cells, and 2--3 short distal cells. Primary stem leaves imbricate, lanceolate-acuminate, more or less auriculate at base, concave, margins plane, or recurved in part distally, papillose-denticulate; costa slender; medial cells short-linear, in rows diverging from costa, seriate-papillose; alar cells differentiated. Branch leaves similar to stem leaves, imbricate, apex sometimes 1-seriate-filiform. Sexual condition apparently dioicous. Capsule immersed or exserted, erect; operculum rostrate; exostome and endostome papillose; cilia inconspicuous. Calyptra cucullate or mitrate, usually hairy. Spores papillose.


Species ca. 80 (1 in the flora); tropical and subtropical regions almost worldwide.


W. R. Buck (1994) proposed the merging of Papillaria with a related genus, Meteorium, but Papillaria can be defined adequately by the combination of teretely foliated stems and branches, concave leaves with auriculate bases, seriately pluripapillose leaf cells in rows diverging from the costa, and tendency toward recurved distal leaf margins.


1. Papillaria nigrescens (Hedwig) A. Jaeger, Ber. Tätigk. St. Gallischen Naturwiss. Ges. 1875--1876: 265. 1877. (Ad. 2: 169)


Hypnum nigrescens Swartz ex Hedwig, Sp. Musc. 250. 1801; Papillaria nigrescens subsp. donnellii Kindberg; P. nigrescens var. donnellii Austin; Tricholepis nigrescens (Hedwig) Grout; T. nigrescens var. donnellii Grout


Plants yellowish green, often black in older portions. Primary stems conspicuous. Branches short or sometimes elongate and pendent; slender fragile flagelliferous branchlets often present in leaf axils; commonly some branches naked distally except for a terminal tuft of leaves. Primary stem leaves 1--1.5 mm, broadly acuminate, apex acute. Branch leaves similar to stem leaves, 1--1.5 mm, acuminate, sometimes with long 1-seriate-filiform apex; costa reaching midleaf or beyond; medial cells 25--40 \um, commonly with 4--6 seriate papillae ad- and abaxially, papillae occasionally on sutures between adjacent cells.


Sporophytes absent in flora area. Tree bark in shaded humid hammocks and swamp forests, rarely on limestone or soil; 0--10 m; Fla., La.; Mexico; West Indies; Central America; South America.


The stems and branches of P. nigrescens are terete-foliate, dull yellowish-green, and often blackish in older portions. The plants creep over the bark substrate and sometimes have elongate irregularly branched pendent branches. In some colonies all leaves of all plants have long uniseriate-filiform apices so that the plants very much resemble Barbella pendula. Although perigonia are present in some specimens no perichaetia or sporophytes have been found in plants from the flora area. Plants referred to the variety donnellii represent an apparently casually expressed form in which some branches lose their leaves except for a tuft at the tip of the otherwise naked seta-like branch. This moss is frequent and often locally abundant throughout most of Florida, much less so in southern Louisiana.


2. BARBELLA Fleischer in V. F. Brotherus in A. Engler & K. Prantl, Nat. Pflanzenfam. 1(3): 823. 1906 * [Diminutive of Latin barb, beard, alluding to the pendent secondary stems]


Plants slender, dull, with long, pendent branches, green to yellowish-green. Primary stems irregularly branched; axillary hairs of 4--7 short cells, proximal cells brownish in older leaf axils. Primary stem leaves loosely imbricate, triangular-acuminate, plane, margins plane, serrate; costa faint or strong, rarely lacking; medial cells linear, not in rows diverging from costa, mostly with 1--3 seriate papillae ad- and abaxially, rarely smooth, alar cells differentiated. Branch leaves similar to stem leaves, spreading-complanate proximally, becoming smaller and loosely imbricate distally. Sexual condition dioicous, rarely autoicous. Capsule exserted, ovoid-cylindric; operculum short-rostrate; exostome teeth slender, papillose or rarely smooth; endostome segments papillose. Calyptra mitrate or cucullate, smooth or pilose. Spores smooth or granular.


Species ca. 40 (1 in the flora): tropical and subtropical regions nearly worldwide.


1. Barbella pendula (Sullivant) Fleischer, Musci Fl. Buitenzorg 3: 812. 1908


Meteorium pendulum Sullivant in A. Gray, Man. Bot. N.U. States, ed. 2, 81. 1856; Neodicladiella pendula (Sullivant) W. R. Buck


Plants green. Primary stems inconspicuous. Primary stem leaves 1.5--2 mm, triangular-acuminate, apex filiform. Branches slender, pendent, to 15 cm or more. Branch leaves proximally triangular acuminate, 2 mm, distally slenderly acuminate, 1--1.5 mm, apex 1-seriate-filiform; costa slender, ending at or before midleaf; medial cells 60 \um; mostly with (2--)3--5 seriate papillae ad- and abaxially; alar cells quadrate. Sexual condition apparently autoicous. Perigonia not seen. Perichaetia mostly on proximal portions of branches. Seta brown, 2--2.5 mm. Capsule dark brown at maturity, ovoid, 1--1.5 mm; operculum obliquely conic-rostrate, 0.7--0.8 mm. Calyptra conic-mitrate, erose proximally, smooth. Spores smooth to granular, 15--26 \um.


Capsules mature March. Deep cool shady humid ravines in deciduous forests; on Arundinaria, shrubs, tree branches, and exposed roots along ravines; 10--20 m; La., Miss.; Mexico; Asia.


Barbella pendula is not common in the flora area but may be locally abundant. The delicate yellowish green plants dangle in conspicuous tangled festoons in their ravine-bottom habitat. The striking habit of the plants and the somewhat dimorphic branch leaves---the distal with uniseriate filiform apices---make the species unmistakable. This species has been reported from Florida, but the McFarlin specimen (MICH!) is slender branchlets of Papillaria nigrescens and the Donnell Smith specimen (US) is a single short branch “found with M. donnellii [Papillaria donnellii = P. nigrescens] from the Everglades . . . .” It is possible that B. pendula did exist at one time in southern Florida but if so, it has never been found there again. It is far more likely that the tiny scrap of B. pendula constituting the Donnell Smith specimen was accidentally introduced into the Donnell Smith material of P. nigrescens. Perigonia have never been found in specimens (some abundantly fruiting) of B. pendula from the flora area.


SELECTED REFERENCE Reese, W. D. 1966. Barbella pendula (Sull.) Fleisch, a review of its distribution and comments on related species. Bryologist 69: 208--213.

3. ZELOMETEORIUM Manuel, J. Hattori Bot. Lab. 43: 110. 1977 * [Greek zelo, emulate, rival, and Meteorium, alluding to the genus Meteoriopsis, from which Zelometeorium was segregated]


Plants medium-sized, glossy, with pendent branches, green to yellowish green. Primary stems irregularly to regularly branched, axillary hairs 1--3-celled, proximal cell short, brownish, distal cells long. Primary stem leaves loosely spreading to squarrose, ovate-acuminate, somewhat auriculate, concave, margins plane, entire to serrulate; costa slender; medial cells linear, smooth; alar cells sometimes differentiated. Branch leaves similar to stem leaves, spreading to somewhat squarrose. Sexual condition apparently dioicous. Capsule exserted, oblong; operculum conic-rostrate; exostome teeth narrowly lanceolate, smooth to papillose; endostome segments papillose; cilia lacking. Calyptra mitrate, pilose. Spores smooth to scabrate.


Species 5 (1 in the flora): tropical regions of the Americas and Africa.


SELECTED REFERENCE Manuel, M. G. 1977. A monograph of the genus Zelometeorium Manuel. gen. nov. (Bryopsida: Meteoriaceae). J. Hattori Bot. Lab. 43: 107--126.


1. Zelometeorium patulum (Hedwig) Manuel, J. Hattori Bot. Lab. 43: 118. 1977


Hypnum patulum Hedwig, Sp. Musc. 279. 1801; Meteoriopsis patula (Hedwig) Brotherus


Plants yellowish green. Primary stems inconspicuous. Branches pendent, terete, to 12 cm or more long, irregularly branched, forming intricate tangles, sometimes distally filiform. Primary stem leaves spreading-squarrose, 1.5--2 mm, broadly acuminate, apex slender. Branch leaves similar to stem leaves, about 1 mm, sometimes with 1-seriate-filiform apex; costa slender, reaching above midleaf; medial cells linear, 65 \um; alar cells subquadrate in small groups.


Sporophytes absent in flora area. Shrubs in humid evergreen hammock forests; 0 m; Fla.; Mexico; West Indies; Central America; South America.


Plants of Z. patula are easy to recognize, being smooth, glossy, and pendent in loose tangles, with usually distinctly spreading-squarrose leaves. In the flora area this moss is known only from Collier and Dade counties, Florida. There is only one recent collection (1993) of this moss from Florida (since 1940), and the species is perhaps in danger of extinction in the flora area due to destruction of habitat.




Manuel, M. G. 1977a. A monograph of the genus Zelometeorium Manuel, gen. nov. (Bryopsida, Meteoriaceae). J. Hattori Bot. Lab. 43: 107-126.