Thuidium

Thuidium is a genus of mosses in the family Thuidiaceae. These mosses are typically found growing on rocks, soil, or tree trunks, often in shaded or humus-rich environments. They are distributed widely across the globe, with a diverse range of species. Thuidium mosses are generally slender-stalked, producing feathery or laxly branched shoots with often crowded leaves.

Morphologically, Thuidium mosses are characterized by the formation of perichaetia, which are long, hairy or papillose leaves produced by female plants ahead of the sets. Perichaetial leaves are often distinctive in shape, size and color compared to other leaves on the same plant. Male and female plants can often be distinguished based on their leaf morphology and other features.

The capillitium of Thuidium mosses is relatively delicate and often visible to the naked eye as a tangential layer. It usually takes the form of a delicate lace-like meshwork underneath the soral layer, separating the sporophyte from the seta. Thuidium species grow in a variety of ecosystems, including boreal forests, mountain meadows, and tropical lowland rainforests.

Thuidium mosses are relatively small compared to some other types of mosses, but they often form substantial cushions or patches. Soil and rock-dwelling species typically have a low growth habit, with plants densely packed or more open as per their habitat. More compact forms exist among species found in prostrate epiphytic grower clumps.

Thuidium species are primarily non-vascular, multicellular plants. They typically obtain moisture and nutrients through environmental actions such as rain and mist.