Stems: with branches to 1 cm, simple or 2-fid. Branch: leaves 0.7â1.8 mm; basal laminal cells tuberculate or smooth, walls thick; distal cells bulging mid leaf, grading to papillose-bulging at tip. Seta: dextrorse. Capsule: with exothecial cells not differentiated; stomata at capsule base; exostome teeth rudimentary, delicate, pale yellow. Spores: 22â32 µm, densely papillose. Phenology: Capsules mature spring. Habitat: Branches and trunks of trees Elevation: low elevations Distribution: Fla., La., Miss., Mexico, West Indies, Central America, South America.
Discussion: Macromitrium richardii is distinguished from other mosses with similar creeping stems and erect branches by its non-rugose, inrolled leaves and uniformly elongate basal laminal cells. The papillose-bulging distal laminal cells and autoicous sexual condition distinguish M. richardii from other species of Macromitrium in the tropical portions of its range.