Moss among three divisions: Bryophyta, Marchantiophyta and Anthocerotophyta. The current circumscription of Bryophyta includes only the mosses. The mosses, now division Bryophyta (Bryophyta sensu stricto), are divided into eight classes: Six of the eight classes contain only one or two genera each. Polytrichopsida includes 23 genera, and Bryopsida includes the majority of moss diversity with over 95% of moss species belonging to this class. The Sphagnopsida, the peat-mosses, comprise the two living genera "Ambuchanania" and "Sphagnum", as well as fossil taxa. However, the genus "Sphagnum" is a diverse, widespread, and economically important one. These large mosses form extensive acidic bogs in
Sphagnum palustre marshy meadows, but rarely in moors. The species often forms large carpets, sometimes bulge-shaped. It is often accompanied by "Sphagnum fimbriatum", "Sphagnum subnitens", and "Sphagnum squarrosum". "Sphagnum palustre" is invading the native habitat at Ka'ala, O'ahu, Hawai'i. It became established after a sample was brought to the island by a botanist in 1960. Although the environment does not allow the plant to reproduce sexually via spores, it is capable of spreading through vegetative reproduction. It currently occupies an area estimated at 17.3 acres. Coordinated eradication efforts have proved difficult. Sphagnum palustre is found all over the British Isles. It is