Ecology: Dry inter-Andean valleys, open montane to páramo and puna; on soil and soil covered rocks. Elevation: 1230-3900 m (Venezuela: 1230-1450 m, Colombia: 2650 m, Ecuador: [Galapagos Islands 250 m], Peru: 3700-3900 m, Bolivia: 1850-2700 m). Distribution: Pantropical; including Mexico, Central America, tropical Andes, Brazil.
Brachymenium exile is a small statured plant, with ovate leaves ca. 1 mm long, strong strong percurrent to short excurrent costa, marginal border absent or weakly developed, and quadrate to short rectangular basal cells. Similar to Bryum chryseum at least with regard to the leaves, but as the name implies the plants are usually golden-yellow, unlike the glossy pale green of Brachymenium exile. See further comments under B. acuminatum. Bryum smaragdinum Müll. Hal., described from Venezuela, is a synonym.