Monographs Details: Fissidens taxifolius Hedw.
Authority: Pursell, Ronald A. 2007. Fissidentaceae. Fl. Neotrop. Monogr. 101 (Published by NYBG Press)
Family:Fissidentaceae
Synonyms:Dicranum taxifolium (Hedw.) F.Weber & D.Mohr, Skitophyllum taxifolium (Hedw.) Bach.Pyl., Schistophyllum taxifolium (Hedw.) Lindb.
Description:Species Description - Plants light to dark green. Stems monomorphic, to 11 mm [1.1 cm] long x 3.5 mm wide, unbranched and branched from older parts; rhizoids basal, smooth, tan to reddish; axillary hyaline nodules absent; epidermis and outer 1-2 tiers of cortical cells small, incrassate, pigmented; inner cortical cells larger, thin-walled, hyaline; central strand present. Leaves ± inrolled from tips, somewhat crisped when dry, usually imbricate, as many as 15 pairs, oblong to lanceolate, obtuse to broadly acute, cuspidate, often undulate in proximal part of dorsal lamina, to 2.7 mm long x 0.6 mm wide; margin evenly serrulate, often crenulate-serrulate on dorsal and ventral laminae, elimbate; costa distinct, ending in cuspidate apex, taxifolius type; dorsal lamina truncate-rounded proximally, not decurrent; vaginant laminae of cauline leaves ± 2/3 leaf length, acute, ± unequal, minor lamina ending near margin-; laminal cells distinct, eguttulate, unistratose, firm-walled, smooth, bulging, 8-11 pm long, marginal ones frequently paler, conspicuously mammillose in vaginant laminae, larger and clearer juxtacostally. Monoicous (rhizautoicous) or dioicous (?); perigonia terminal on short branches at base of longer stems; perichaetia on short, proximal, axillary branches. Sporophytes 1 per perichaetium, yellow-orange; seta smooth, to 17 mm long; theca exserted, ± inclined, ± arcuate, bilaterally symmetric, to 1.9 mm long, stomatose, exothecial cells quadrate to oblong, longitudinal walls thicker than transverse walls; peristome taxifolius type; operculum conic, short-rostrate, to 1 mm long. Spores finely papillose, 13-18 pm diam. Calyptra not seen in Neotropical collections. In specimens from the United States the calyptra is cucullate, smooth, to 2 mm long. n = 9, 12, 16 (Fritsch, 1991).

Discussion:Fissidens taxifalius, widespread in the Northern Hemisphere, is found at moderately high elevations in the Neotropics. The species is distinguished by its evenly serrulate leaf margin, conspicuously mammillose vaginant laminal cells, stout costa extending into a cusp, and short perichaetial branches in the proximal parts of stems. Fissidens taxifolius can be confused with F. bourgaeanus, but plants of this latter species are larger, lack the mammillose vaginant laminal cells, and have 2-5 rows of thick, often bis-tratose, marginal cells that form a dark border on the leaves.
Distribution:Bío-Bío Chile South America| Elías Piña Dominican Republic South America| Chiapas Mexico North America| Querétaro Mexico North America| Tamaulipas Mexico North America| Veracruz Mexico North America| Alta Verapaz Guatemala Central America| Baja Verapaz Guatemala Central America| Huehuetenango Guatemala Central America| Quezaltenango Guatemala Central America| Sacatepéquez Guatemala Central America| Zacapa Guatemala Central America| Lempira Honduras Central America| Bermuda South America| Jamaica South America| Ouest Haiti South America| Independencia Dominican Republic South America| La Vega Dominican Republic South America| Pedernales Dominican Republic South America| Puerto Plata Dominican Republic South America| Rio Grande do Sul Brazil South America|