Fissidens Moss

Fissidens taxifolius is characterized by its highly mammillose cells of the vaginant laminae.

Fissidens taxifolius is distinguished by evenly serrulate or crenulate-serrulate leaf margin, stout costa ending in leaf cusp, conspicuous mammillose cells in the vaginant laminae, and sporophytes on short branches in the axils of proximal leaves. It can be confused with F. bushii, but that species is smaller, has costa shorter, and cells in the vaginant laminae have small, more or less inconspicuous papillae in the corners of the walls. Fissidens taxifolius usually occurs on shaded, damp soil or humus, whereas F. bushii is usually found on disturbed soil in woods, along paths, and in road cuts. Fissidens clebschii is considered to be a freakish expression of F. taxifolius (R. A. Pursell 2003).

Plants medium-sized, growing in dense tufts. Leafy stems simple, occasionally branched, 4.5–16.0 mm long, 2.0–4.6 mm wide; axillary hyaline nodules not developed; cortical stem-cells small and thick-walled, central strand not well developed. Leaves in 6–17 pairs, more or less overlapping, middle to upper leaves ovate-lanceolate, 1.6–3.3 mm × 0.5–0.8 mm, acute to mucronate at apex; base of dorsal laminae usually rounded, sometimes broadly wedge-shaped; vaginant laminae 1/2 –3/5 the leaf length, slightly unequal; costa stout, percurrent to shortly excurrent; margins serrulate; cells of apical and dorsal laminae rounded-hexagonal to hexagonal, 7–11 µm long, thin-walled, mammillose, obscure; cells of vaginant laminae similar to those of apical and dorsal laminae, but with thicker walls and higher mammillae, larger toward the base near costa. Dioicous. Female inflorescences lateral. Perichaetial leaves differentiated, narrowly lanceolate, ca. 1.3 mm long. Archegonia 370–426 µm long. Setae 11–16 mm long; capsules horizontal to inclined, asymmetrical, curved, constricted below capsule mouth when dry; urns ca. 1 mm long; exothecial cells rectangular-hexagonal, with thickened longitudinal and thin transverse walls; opercula long rostrate; peristome teeth 0.56–0.63 mm long, 127–156 µm wide at base, with distinct projections on the articulations. Spores 10–18 µm in diameter.

Plants to 11 × 3.5 mm. Stem mostly branched; axillary hyaline nodules absent; central strand present. Leaves as many as 15 pairs, often undulate, oblong to lanceolate, obtuse to broadly acute, cuspidate, to 2.7 mm × 0.6 mm; dorsal lamina truncate-rounded proximally, ending at insertion, not decurrent; vaginant laminae ²/3 the leaf length, ± equal, minor lamina ending on or near margin; margin evenly serrulate, often crenulate-serrulate on dorsal and ventral laminae, elimbate; costa ending in cuspidate apex, taxifolius-type; laminal cells 1-stratose, distinct, smooth, bulging, firm-walled, irregularly hexagonal, 8-11 µm frequently paler at margin, conspicuously mammillose in vaginant laminae, larger and clearer juxtacostally. Sexual condition rhizautoicous; perigonia on short branches proximal to elongate stems; perichaetia on short, proximal, axillary branches. Sporophytes 1 per perichaetium. Seta to 17 mm. Capsule theca slightly inclined, slightly arcuate, bilaterally symmetric, to 1.5 mm; peristome taxifolius-type; operculum to 1 mm. Calyptra cucullate, smooth, to 2 mm. Spores 13-18 µm.

Distribution: widely distributed in the world.

Habitat: on soil, rarely on rocks.

Fissidens sylvaticus Griff., Calcutta J. Nat. Hist. 2: 507. 1842.

Fissidens clebschii Steere

Fissidens taxifolius Hedw. Sp. Muse. 155. 1801
Plants Ught green, darker with age, 5-20 mm. high; stems rather stout, sparingly branched from the base; leaves close, overlapping, in many pairs, largest in the middle of the stem, ± 2 mm. long, oblong-cult r if orm, roundedobtuse and apiculate to subacute, finely and evenly crenulate above with projecting cell-angles, the costa strong, in weU developed mature plants excurrent into a short mucro, in lower leaves and on depauperate or tmdeveloped plants often merely percurrent; vaginant laminae one-half to two-thirds the length of the leaf; dorsal lamina ending abruptly, usuaUy reaching the stem; upper median leaf-ceUs 7-10 ju, bulgingmamiUose, smaller and often somewhat Hghter-colored at the margins, larger near the costa; perichaetial leaves often with terminal and dorsal lamina narrow, Unear or sword-shaped, or almost lacking; cf buds on short branches rooting at base; sporophyte axiUary near the base; seta 8-15 mm. long, ascending, flexuous; capsule oblong, contracted under the mouth when dry, the urn db 1.5 mm. long, somewhat incUned to nearly pendulous, mostly somewhat 59. F. cristatus.
60. F. adiantoides. curved and asymmetric, the exothecial cells oblong to subquadrate, incrassate, with many rows of smaller very incrassate isodiametric cells below the mouth; calyptra covering nearly half the urn, split on one side; operculum conic, long, obhquely rostrate, the beak fully the length of the urn; peristometeeth deep red, the divisions strongly nodtalose and marked with very fine oblique lines between the nodes; spores 15-20 m in diameter, maturing from November to March.
Type locality: Europe.
Distribution: On damp shaded soil; Canada and the eastern United States, south to central Florida and Missouri; Carr Peak, Huachuca Mts., Arizona {Goodding).

Fissidens taxifolius is a species of moss in the Fissidentaceae family. It has a cosmopolitan distribution.

Fissidens taxifolius is known to be able to use artificial light to grow in places which are otherwise devoid of natural light, such as Crystal Cave in Wisconsin.