Polytrichidae

The Polytrichidae are a small subclass of mosses that includes the orders Polytrichales and Dawsoniales. These mosses, often referred to as hair-cap mosses, are found in various habitats, including peat bogs and acidic soils. A widely distributed species is P. commune, which can grow quite tall and form extensive beds.12

Key characteristics of Polytrichidae include their phyllids (leaves) which have sheathed bases and pointed tips. They reproduce sexually, with male and female reproductive organs on separate plants. The capsules, or spore cases, resemble grains of wheat and are covered by a hairy calyptra. Internally, the stems of Polytrichidae mosses feature a complex conducting strand, analogous to vascular plants, composed of water-conducting hydroids and sugar-conducting leptoids.23