Monographs Details: Fissidens leptophyllus Mont.
Authority: Pursell, Ronald A. 2007. Fissidentaceae. Fl. Neotrop. Monogr. 101 (Published by NYBG Press)
Family:Fissidentaceae
Synonyms:Fissidens micropyxis Broth., Fissidens subflexinervis Broth., Fissidens reesei H.A.Crum & L.E.Anderson
Description:Species Description - Plants light to dark green. Stems monomorphic, unbranched to sparingly branched, to 15 mm [1.5 cm] long x 3.0 mm wide; rhizoids basal, smooth, 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 absent. Leaves ± crispate when dry, distant to loosely imbricate, as many as 30 pairs, oblong to oblanceolate, broadly acute to rounded, 0.9-1.2 mm long x 0.3-0.6 mm wide, perichaetial leaves longest; margin crenulate-serrulate on dorsal and ventral laminae, ± entire and limbate on proximal 1/2 or less of vaginant laminae of most leaves, limbidial cells unistratose; costa ending 2-6 cells below leaf apex, bryoides type; dorsal lamina narrowed slightly, ending at insertion; vaginant laminae of cauline leaves ± 1/2-2/3 leaf length, acute, ± equal, or unequal, minor lamina ending ± midway between costa and leaf margin; laminal cells distinct, eguttulate, unistratose, firm-walled, mammillose (mammillae often difficult to discern), irregularly quadrate, 7-10 µm long, juxtacostal cells in lower parts of vaginant laminae often hyaline, enlarged, ± oblong, to 33 µm long. Monoicous (gonioautoicous, perhaps rhizautoicous); perigonia gemmiform, axillary; perichaetia terminal on stems. Sporophytes 1 per perichaetium, yellow, darkening with age; seta smooth, 1.5-3.5 mm long; theca exserted, erect, radially symmetric, 0.5 mm long, stomatose, exothecial cells ± quadrate, collenchymatous; peristome scariosus type; operculum conic, long-rostrate, 0.4-0.5 mm long. Spores finely papillose, 12-18 µm diam. Calyptra cucullate, smooth, 0.3-0.5 mm long, covering only rostrum.

Discussion:Fissidens leptophyllus is characterized by its broadly acute to obtuse leaves, a costa ending 2 or more cells below the apex, mammillose laminal cells (mammillae are often difficult to discern without sectioning), and a limbidium restricted to the lower half of the vaginant laminae of most leaves. Fissiden sub-marginatus, with which the species can be confused, has a more sharply acute leaf, percurrent to excurrent costa, and limbidium that extends the entire length, or nearly so, of the vaginant laminae. Fissidens leptophyllus could also be confused with expressions of F. bryoides of subgenus Fissidens section Fissidens if the mammillae are not recognized.
Distribution:Trinidad and Tobago South America| Honduras Central America| Limón Costa Rica Central America| Puntarenas Costa Rica Central America| Amazonas Colombia South America| Amazonas Venezuela South America| Sipaliwini Suriname South America| Brokopondo Suriname South America| French Guiana South America| Morona-Santiago Ecuador South America| Acre Brazil South America| Pará Brazil South America| São Paulo Brazil South America| Santa Cruz Bolivia South America| Central Paraguay South America| Concepción Paraguay South America|