Mosses are small, non-vascular flowerless plants in the taxonomic division Bryophytasensu stricto. Bryophyta may also refer to the parent group bryophytes, which comprise liverworts, mosses, and hornworts. Mosses typically form dense green clumps or mats, often in damp or shady locations. The individual plants are usually composed of simple leaves that are generally only one cell thick, attached to a stem that may be branched or unbranched and has only a limited role in conducting water and nutrients. Although some species have conducting tissues, these are generally poorly developed and structurally different from similar tissue found in vascular plants. Mosses do not have seeds and after fertilisation develop sporophytes with unbranched stalks topped with single capsules containing spores. They are typically 0.2–10 cm (0.1–3.9 in) tall, though some species are much larger. Dawsonia, the tallest moss in the world, can grow to 50 cm (20 in) in height. There are approximately 12,000 species.
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.
Adiantum capillus-veneris, the Southern maidenhair fern, black maidenhair fern, maidenhair fern, and venus hair fern, is a species of ferns in the genus Adiantum and the family Pteridaceae with a subcosmopolitan worldwide distribution. It is cultivated as a popular garden fern and houseplant.
Marchantiales is an order of thallose liverworts that includes species like Marchantia polymorpha, a widespread plant often found beside rivers, and Lunularia cruciata, a common and often troublesome weed in moist, temperate gardens and greenhouses.
Lunularia cruciata, the crescent-cup liverwort, is a liverwort of the order Marchantiales, and the only species in the genus Lunularia and family Lunulariaceae. The name, from Latin luna, moon, refers to the moon-shaped gemma cups.
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.
Conocephalum is a genus of complex thalloid liverworts in the order Marchantiales and is the only extant genus in the family Conocephalaceae. Some species of Conocephalum are assigned to the Conocephalum conicum complex, which includes several cryptic species. Conocephalum species are large liverworts with distinct patterns on the upper thallus, giving the appearance of snakeskin. The species Conocephalum conicum is named for its cone-shaped reproductive structures, called archegoniophores. Common names include snakeskin liverwort, great scented liverwort and cat-tongue liverwort.
Monoicy is a sexual system in haploid plants where both sperm and eggs are produced on the same gametophyte, in contrast with dioicy, where each gametophyte produces only sperm or eggs but never both. Both monoicous and dioicous gametophytes produce gametes in gametangia by mitosis rather than meiosis, so that sperm and eggs are genetically identical with their parent gametophyte.
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.
Phycolepidozia exigua was thought to be the only species of liverwort in the genus Phycolepidozia and family Phycolepidoziaceae. Until another species was found. Phycolepidozia exigua is endemic to Dominica, where it is critically endangered. Its natural habitat is subtropical or tropical moist lowland forests.
Haplomitriopsida is a newly recognized class of liverworts comprising fifteen species in three genera. Recent cladistic analyses of nuclear, mitochondrial, and plastid gene sequences place this monophyletic group as the basal sister group to all other liverworts. The group thus provides a unique insight into the early evolution of liverworts in particular and of land plants in general.
Marchantia polymorpha is a species of large thalloid liverwort in the class Marchantiopsida. M. polymorpha is highly variable in appearance and contains several subspecies. This species is dioicous, having separate male and female plants. M. polymorpha has a wide distribution and is found worldwide. Common names include common liverwort or umbrella liverwort.
Zygodon gracilis, the slender yokemoss, is a moss species in the genus Zygodon. It is a rare lithophyte found to only grow on certain localities of limestone outcrops that has high calcium carbonate content. The current global conservation status of Z. gracilis is considered to be "imperiled".
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.
Conocephalum conicum, also known as the great scented liverwort or snakeskin liverwort, is a liverwort species in the genus Conocephalum. C. conicum is part of the Conocephalum conicum complex, which includes several cryptic species. The name C. conicum refers to the cone-shaped archegoniophore, which bear sporangia.
Petalophyllum ralfsii, the petalwort, is a liverwort of the order Fossombroniales. It is a small green bryophyte that occurs in the Mediterranean region as far east as Turkey, and along the Atlantic coast of Europe as far as northwest Scotland. It grows primarily on moist sand dunes.
Conocephalum supradecompositum is a species of thalloid liverwort in the genus Conocephalum, of the order Marchantiales and the family Conocephalaceae. C. supradecompositum has a distribution that is mainly restricted to China and Japan. C. supradecompositum has very distinct chemical composition from the species Conocephalumconicum.
The oil bodies of liverworts, occasionally dubbed “complex” for distinction, are unique organelles exclusive to the Marchantiophyta. They are markedly different from the oil bodies found in algae and other plants in that they are membrane-bound, and are not associated with food storage. The organelles are variable and present in an estimated 90% of liverwort species, often proving taxonomically relevant. As a whole, the formation and function of the organelles are poorly understood. Complex oil bodies are recognized as sites of isoprenoid biosynthesis and essential oil accumulation, and have been implicated with anti-herbivory, desiccation tolerance, and photo-protection.
Endogemma is a monotypic genus of liverworts belonging to the family Endogemmataceae and subclass of Jungermanniineae.
