The Marchantiophyta are a division of non-vascular land plants commonly referred to as hepatics or liverworts. Like mosses and hornworts, they have a gametophyte-dominant life cycle, in which cells of the plant carry only a single set of genetic information.
Jungermanniales is the largest order of liverworts. They are distinctive among the liverworts for having thin leaf-like flaps on either side of the stem. Most other liverworts are thalloid, with no leaves. Due to their dorsiventral organization and scale-like, overlapping leaves, the Jungermanniales are sometimes called "scale-mosses".
Metzgeriales is an order of liverworts. The group is sometimes called the simple thalloid liverworts: "thalloid" because the members lack structures resembling stems or leaves, and "simple" because their tissues are thin and relatively undifferentiated. All species in the order have a small gametophyte stage and a smaller, relatively short-lived, spore-bearing stage. Although these plants are almost entirely restricted to regions with high humidity or readily available moisture, the group as a whole is widely distributed, and occurs on every continent except Antarctica.
Lejeuneaceae is the largest family of liverworts. Most of its members are epiphytes found in the tropics, while others can be found in temperate regions.
Cavicularia densa is the only species in the liverwort genus Cavicularia. The species was first described in 1897 by Franz Stephani, and is endemic to Japan, where it grows on fine moist soil.
Treubiaceae is a family of liverworts in the order Treubiales. Species are large and leafy, and were previously classified among the Metzgeriales.
Phycolepidozia exigua is the only species of liverwort in the genus Phycolepidozia and family Phycolepidoziaceae. It is endemic to Dominica, where it is critically endangered. Its natural habitat is subtropical or tropical moist lowland forests.
Blasiales is an order of liverworts with a single living family and two species. The order has traditionally been classified among the Metzgeriales, but molecular cladistics suggests a placement at the base of the Marchantiopsida.
Apotreubia is a genus of liverworts in the family Treubiaceae. There are four species, including: Apotreubia nana, which is found in subalpine New Guinea, and Apotreubia pusilla, which has a disjunct distribution between eastern Asia and British Columbia.
Treubia is a genus of liverworts in the family Treubiaceae. There are seven species, all of which are restricted to the southern hemisphere. Five of the species occur in Australasia and the other occurs in Chile. All species are dioicous, with separate male and female gametophytes.
Phyllothallia is a small genus of liverworts of the Southern Hemisphere. It is classified in the order Pallaviciniales and is the only member of the family Phyllothalliaceae within that order. Unlike most members of the Metzgeriales, Phyllothallia has a leafy appearance. The genus has a disjunct distribution, with the species Phyllothallia nivicola found in New Zealand while the other species in the genus, Phyllothallia fuegiana, occurs in Tierra del Fuego.
Aneura mirabilis is a species of liverworts in the family Aneuraceae. It was first described in 1933, as Cryptothallus mirabilis. Plants of this species are white as a result of lacking chlorophyll, and their plastids do not differentiate into chloroplasts.
Makinoa crispata is the only species of liverwort in the genus Makinoa and family Makinoaceae. The genus Verdoornia was formerly included in this family, but has been transferred to the family Aneuraceae on the basis of recent cladistic analysis of genetic sequences.
Ptilidium is a genus of liverwort, and is the only genus in family Ptilidiaceae. It includes only three species: Ptilidium californicum, Ptilidium ciliare, and Ptilidium pulcherrimum. The genus is distributed throughout the arctic and subarctic, with disjunct populations in New Zealand and Tierra del Fuego. Molecular analysis suggests that the genus has few close relatives and diverged from other leafy liverworts early in their evolution.
Neotrichocoleaceae is a family of liverworts in order Ptilidiales. It is closely related to the genera Ptilidium and Herzogianthus.
Riella is a genus in the liverwort family Riellaceae, and includes about eighteen species. Plants in the genus are small and grow submerged in shallow temporary pools. Although the genus is widely distributed in the Northern Hemisphere, locating populations is often difficult. Its occurrence is sporadic and local, and the tiny plants are ephemeral. The ornamented spores remain viable for several years, allowing the plants to survive annual drying of their habitat. The plants are easily grown in laboratory cultures.
Petalophyllum, or petalwort, is a genus of liverworts in the order Fossombroniales.
Petalophyllum americanum, common name petalwort, is a species of liverwort in the order Fossombroniales. It is endemic to the Gulf Coast of the United States in Arkansas, Louisiana, Mississippi, and Texas. It was first described as the European species Petalophyllum ralfsii in 1919, but a detailed study later showed that the North American form is a distinct species.
Ricciocarpos natans is the only species in the genus Ricciocarpos, a genus of liverworts in the family Ricciaceae. It was formerly listed in 1759 as a species of Riccia by Linnaeus, but then assigned to a new genus of its own in 1829 by August Carl Joseph Corda.
Polytrichastrum formosum, commonly known as the bank haircap moss is a species of moss belonging to the family Polytrichaceae.
