Monographs Details: Fissidens inaequalis Mitt.
Authority: Pursell, Ronald A. 2007. Fissidentaceae. Fl. Neotrop. Monogr. 101 (Published by NYBG Press)
Synonyms:Conomitrium inaequale (Mitt.) A.Jaeger, Fissidens occultus Broth., Conomitrium latiusculum Müll.Hal., Fissidens latiusculus (Müll.Hal.) Paris, Conomitrium elachistophyllum Müll.Hal., Conomitrium perpygmaeum Müll.Hal., Fissidens perpygmaeus (Müll.Hal.) Broth., Fissidens macroblastus R.S.Williams, Fissidens perminutus Broth., Fissidens pauperculus var. surinamensis Florsch.
Description:Species Description - Plants pale green, often castaneous in costa. Stems monomorphic, unbranched to sparingly branched, 2.5-6.0 mm long x ± 0.2 mm wide; rhizoids basal and axillary, smooth, light-brown; axillary hyaline nodules absent; epidermis and outer tier of cortical cells small, incrassate, pigmented; inner cortical cells larger, thin-walled, hyaline; central strand present or absent. Leaves ± crispate, ± rolled inward longitudinally toward costa when dry, usually distant, as many as 15 pairs, oblanceolate to oblong, obtuse to broadly acute, often apiculate, 0.7-1.6 mm long x 0.2-0.4 mm wide, perichaetial ones longest; margin ± entire to evenly crenate-serrate, elimbate; costa ending 2-9 or more cells below apex to percurrent, bryoides type; dorsal lamina narrowed to insertion, often rounded, not decurrent; vaginant laminae of cauline leaves 1/3 - ± 1/2 leaf length, variable, acute, ± equal, minor lamina ending 1/2 or less the distance between margin and costa or rounded and free, broad and retuse in perigonial and perichaetial leaves; laminal cells distinct, often guttulate, firm-walled, smooth, hexagonal to elongate-hexagonal to oblong, especially along costa, 11-65 µm long x 11-18 µm wide, marginal 1-2 rows usually conspicuously smaller, 10-18 µm long. Monoicous (gonioau-toicous, rhizautoicous); perigonia gemmiform, axillary or terminal on stems of ± equal in length to perichaetial stems; perichaetia terminal on stems. Sporophytes 1-2 per perichaetium, yellow, darkening with age; seta to 3 mm long; theca exserted, erect, radially symmetric, stomatose, exothecial cells ± quadrate, collenchymatous; peristome scariosus type; operculum conic, long-rostrate, 0.5-0.8 mm long. Spores smooth, 9-13 µm diam. Calyptra cucullate, smooth, 0.4-0.9 µm, covering only rostrum.

Discussion:Fissidens inaequalis is recognized by its elimbate leaves, dimorphic laminal cells, costa ending 2-9 or more cells below apex to percurrent, and erect, radially symmetric theca. The species can be confused with F. omatus which also has dimorphic laminal cells, but in this species the leaves are limbate on the vaginant laminae and the costa is typically excurrent. The dimorphism of the laminal cells is less conspicuous, and the costa is never more than percurrent in F. inaequalis.
Distribution:Saint-Laurent-du-Maroni French Guiana South America| Upper Demerara-Berbice Guyana South America| Mazaruni-Potaro Guyana South America| Trinidad and Tobago South America| Heredia Costa Rica Central America| Puerto Rico South America| Montserrat South America| Amazonas Colombia South America| Antioquia Colombia South America| Caquetá Colombia South America| Magdalena Colombia South America| Amazonas Venezuela South America| Falcón Venezuela South America| Monagas Venezuela South America| Rupununi Guyana South America| Marowijne Suriname South America| Nickerie Suriname South America| Saramacca Suriname South America| Sipaliwini Suriname South America| Imbabura Ecuador South America| Napo Ecuador South America| Loreto Peru South America| Acre Brazil South America| Amazonas Brazil South America| Pará Brazil South America| Pernambuco Brazil South America| Rondônia Brazil South America| Roraima Brazil South America| São Paulo Brazil South America| La Paz Bolivia South America| Alto Paraná Paraguay South America| Cordillera Paraguay South America|