Sphagnum ones ("Rigida" and "Squarrosa") has been clarified using molecular phylogenetics. All but two species normally identified as "Sphagnum" reside in one clade; two other species have recently been separated into new families within the Sphagnales reflecting an ancestral relationship with the Tasmanian endemic "Ambuchanania" and long phylogenetic distance to the rest of "Sphagnum". Within main clade of "Sphagnum", phylogenetic distance is relatively short, and molecular dating methods suggest nearly all current "Sphagnum" species are descended from a radiation that occurred just 14 million years ago. "Sphagnum" mosses occur mainly in the Northern Hemisphere in peat bogs, conifer forests, and moist
Sphagnum cuspidatum branch leaves can sometimes be faintly serrated. "S. cuspidatum" is a dioecious species. The spores produced are 29-38 µm, covered with large papillae on both surfaces, and appear to be covered in small blisters (pusticulate). "S. cuspidatum" can be found on wet humus under forests and on the bases of trees forming a hummock-hollow complex; in or near bogs. Distinguishing "Sphagnum cuspidatum" from "Sphagnum viride" is sometimes difficult as both occur over a similar geographic range and both grow in wet carpets. "Sphagnum cuspidatum" has narrower branch leaves and usually a distinct red tinge at the branch bases within the