Worldwide, mostly tropical and subtropical regions.
Genera 3, species ca. 150 (2 genera, 11 species in the flora).
The Calymperaceae are defined by clasping leaf bases with cancellinae, absence of stem central strand, usually thickened and toothed leaf margins, mainly tropical-subtropical range, corticolous habitat, and common production of uniseriate leaf-tip gemmae. Plants of the family are specialized for water capture and retention by their sheathing leaf bases, and the large, empty, porose cells of their cancellinae. The habitat is typically on bark but many taxa occur primarily on decaying wood, rock, and soil. Our taxa occur almost exclusively in the southeastern United States.
|1||Plants with sporophytes||> 2|
|1||Plants without sporophytes||> 3|
|2||Calyptra deciduous, cucullate, not clasping the seta, without vertical fissures.||Syrrhopodon|
|2||Calyptra persistent, enclosing the capsule and clasping the seta proximally, with vertical fissures||Calymperes|
|3||Leaves bordered entirely or in part with elongate hyaline cells.||Syrrhopodon|
|3||Leaf margins without elongate hyaline cells||> 4|
|4||Teniolae (intramarginal files of differentiated cells) present at leaf shoulders.||Calymperes|
|4||Teniolae absent||> 5|
|5||Leaves 4-8 mm; margins coarsely toothed and multistratose distally; gemmae adaxial on leaf apex.||Syrrhopodon|
|5||Leaves 1-3 mm; margins entire and 1- to 2-stratose distally; gemmae borne circling apex of excurrent costa.||Calymperes (Calymperes tenerum)|