The Holomitrium-complex (consisting of Holomitrium, Eucamptodontopsis, and Schliephackea) is a group of closely related genera in the Dicranaceae characterized by five features: 1. a strong single costa, 2. well developed alar cells, 3. long, sheathing perichaetial leaves, 4. erect capsules, and 5. undivided peristome teeth. Holomitrium sinuosum is newly described. Dicranoloma brittonae is transferred to Eucamptodontopsis. Holomitrium standleyi is a synonym of H. arboreum. Breedlovea chiapensis is a synonym of Holomitrium pulchellum and the genus Breedlovea is placed into the synonymy of Holomitrium
