Ecology: Lowland to montane forest; on soil, rocks, and base of trees, often along streams. Elevation: 10-3050 m (Venezuela: 120-1800 m, Colombia: 10-3050 m, Ecuador: 245-2750 m, Peru: 660-1200 m, Bolivia: 250-2300 m, Argentina: ? m). Distribution: Widespread in the Neotropics.
Fissidens intramarginatus is characterized by the lanceolate to oblong leaves, acute apex, serrulate to crenulate margins (dorsal & ventral laminae), bordered vaginant laminae and extending a short distance along the ventral laminae), percurrent to short excurrent costa, vaginant laminae 1/2 the leaf length, and firm-walled, pluripapillose laminal cells. Synonyms include Fissidens hancockianus Steere, F. tenuifolius Mitt., F. incacorralis Herzog. The transfer of this species to Fissidens had previously been attributed to Mitten (J. Linn. Soc., Bot. 12: 594. 1869) but Jaeger's transfer occurred three months earlier (cf. Pursell, 1994).
Fissidens intramarginatus se caracteriza por las hojas lanceoladas a oblongas, ápices agudos, márgenes serrulados a crenulados (lámina dorsal y ventral), lámina vaginante bordeada y extendiéndose hasta una distancia corta a lo largo de la lámina ventral), costa percurrente a corto excurrente, lámina vaginante 1/2 del largo de la hoja, y células de la lámina pluripapiloso con paredes firmes.