| Lejeunea drehwaldii | |
|---|---|
Scientific classification  | |
| Kingdom: | Plantae |
| Division: | Marchantiophyta |
| Class: | Jungermanniopsida |
| Order: | Porellales |
| Family: | Lejeuneaceae |
| Genus: | Lejeunea |
| Species: | L. drehwaldii |
| Binomial name | |
| Lejeunea drehwaldii | |
| Synonyms [2] | |
| |
Lejeunea drehwaldii, synonym Sphaerolejeunea umbilicata, is a species of liverwort in the family Lejeuneaceae. [2] It is endemic to Colombia. Its natural habitat is subtropical or tropical moist lowland forests. [1]
The species was first described by T. K. G. Herzog in 1938 as Sphaerolejeunea umbilicata. [3] The genus Sphaerolejeunea was sunk into Lejeunea in 2012. As the name Lejeunea umbilicata was already in use, the replacement name Lejeunea drehwaldii was published. [2] [4]
Lejeunea drehwaldii is a small, bright green liverwort that grows primarily on the surfaces of living leaves (epiphyllous). The plant body, or gametophyte, spreads closely against its substrate, reaching 1.5–2.3 mm in width, and displays extensive branching. Its stem follows a distinctive zig-zag pattern and bears overlapping, rounded leaves arranged in two rows. A unique feature of this species is the presence of specialized dead, transparent (hyaline) cells forming a border around the leaf edges, which is visible in mature leaves but absent in young ones. The species is monoecious (autoicous), meaning both male and female reproductive structures occur on the same plant but in different locations. These reproductive structures are abundantly produced but remain largely hidden when the plant is viewed from above, as they do not project beyond the vegetative leaves. The female reproductive structure (perianth) is cylindrical to egg-shaped and lacks the distinct ridges (keels) found in many related species, instead featuring a unique umbilicate (navel-like) apex formed by a ring of triangular cells. [5]
The spore-producing structure (sporophyte) of L. drehwaldii includes a black, spherical capsule measuring 250–330 micrometres in diameter, which splits into four parts upon maturity. The capsule contains two distinct types of sterile filaments (elaters) that aid in spore dispersal: 18 marginal elaters attached at the edges and 4 additional elaters fixed along their entire length to the inner surface. The spores, which begin germinating while still inside the capsule (precocious germination), are rectangular to irregular in shape and feature a distinctive surface pattern of small, round granules and 3–5 rosette-like structures. [5]
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.
Hornworts are a group of non-vascular Embryophytes constituting the division Anthocerotophyta. The common name refers to the elongated horn-like structure, which is the sporophyte. As in mosses and liverworts, hornworts have a gametophyte-dominant life cycle, in which cells of the plant carry only a single set of genetic information; the flattened, green plant body of a hornwort is the gametophyte stage of the plant.
Marchantia quadrata is a species of liverwort, a simple non-flowering plant that grows as a flat, green, leaf-like structure (thallus) typically found on damp rocks and soil along stream banks in the Northern Hemisphere. The species was originally classified in its own genus Preissia due to its distinctive features, including larger spores and lack of the specialised cup-like reproductive structures common in other liverworts, but genetic studies have shown it belongs within the genus Marchantia. Like most liverworts, it reproduces both sexually, through separate male and female plants that produce umbrella-like reproductive structures, and through regeneration from fragments. The species prefers slightly drier habitats than its relatives and shows significant genetic variation across its range, suggesting it may comprise several distinct but closely related species.
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.
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.
An elater is a cell that is hygroscopic, and therefore will change shape in response to changes in moisture in the environment. Elaters come in a variety of forms, but are always associated with plant spores. In many plants that do not have seeds, they function in dispersing the spores to a new location. Mosses do not have elaters, but peristomes which change shape with changes in humidity or moisture to allow for a gradual release of spores.
Buxbaumia is a genus of twelve species of moss (Bryophyta). It was first named in 1742 by Albrecht von Haller and later brought into modern botanical nomenclature in 1801 by Johann Hedwig to commemorate Johann Christian Buxbaum, a German physician and botanist who discovered the moss in 1712 at the mouth of the Volga River. The moss is microscopic for most of its existence, and plants are noticeable only after they begin to produce their reproductive structures. The asymmetrical spore capsule has a distinctive shape and structure, some features of which appear to be transitional from those in primitive mosses to most modern mosses.
Plant reproduction is the production of new offspring in plants, which can be accomplished by sexual or asexual reproduction. Sexual reproduction produces offspring by the fusion of gametes, resulting in offspring genetically different from either parent. Asexual reproduction produces new individuals without the fusion of gametes, resulting in clonal plants that are genetically identical to the parent plant and each other, unless mutations occur.
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.
Fulfordianthus evansii is a species of liverwort in the family Lejeuneaceae. It is found in Belize, Costa Rica, Guatemala, and Panama. Its natural habitat is subtropical or tropical moist lowland forests.
Biantheridion is a genus of liverwort in the family Anastrophyllaceae. Its only accepted species is Biantheridion undulifolium the marsh flapwort, or marsh earwort. It is found in Austria, China, the Czech Republic, Denmark, Finland, France, Germany, Greenland, North Korea, Norway, Poland, Russia, Sweden, Switzerland, and the United Kingdom. Its natural habitat is swamps. It is threatened by habitat loss.
Schistochila vitreocincta is a species of liverwort in the family Schistochilaceae. Under its synonym Perssoniella vitreocincta it was the only species in the monotypic genus Perssoniella and family Perssoniellaceae. It is endemic to New Caledonia. Its natural habitat is subtropical or tropical dry forests.
Spruceanthus theobromae is a species of liverwort in the family Lejeuneaceae. It is endemic to Ecuador, where it is the only liverwort species known to be endemic to the western foothills of the Ecuadorian Andes.
Kymatocalyx rhizomaticus, synonym Stenorrhipis rhizomatica, is a species of liverwort in the Cephaloziellaceae family. According to the 2000 IUCN Red List, where it was assessed under the synonym Stenorrhipis rhizomatica, it is endemic to Sarawak. Other sources give its distribution as Central America and northern South America.
Aneura mirabilis is a parasitic 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.
Lejeunea hodgsoniana is a species of liverwort in the family Lejeuneaceae. Endemic to New Zealand, it was first recognized in 1980 but not formally described until 2013. The plant forms bright green mats up to 7 centimetres in diameter on tree bark and occasionally on rocks. The species is found from the Kermadec Islands in the north to the Chatham Islands in the south, primarily in coastal and lowland areas below 100 metres elevation. It is distinguished from related species by its relatively large size, multi-celled tooth on the leaf lobule, and deeply divided underleaves with pointed tips. While showing a particular affinity for mahoe trees, it grows on various native and introduced trees and is considered "Not Threatened" under the New Zealand Threat Classification System due to its abundance within its range and ability to grow in both pristine and disturbed habitats.
Acrobolbus pseudosaccatus, synonym Tylimanthus pseudosaccatus, is a bryophyte, a species from the liverwort family Acrobolbaceae. The family grows on logs, rocks, and soil. Under certain circumstances, however, they are epiphyte, growing on other plant species.
Drepanolejeunea senticosa is a critically endangered species of liverwort in the family Lejeuneaceae, endemic to Cuba. The species is epiphyllous, meaning it grows on the surfaces of living leaves, and is found in subtropical/tropical moist lowland forest habitats. While male specimens have been frequently observed, the species' perianth and capsule remain undescribed.
Nowellia curvifolia is a species of liverwort belonging to the family Cephaloziaceae. It is a small, delicate plant that forms prostrate growths on rotting logs in forests throughout the northern temperate and subarctic regions. The species is distinguished by its distinctive billowed leaves arranged in two rows, each divided into two pointed lobes with the lower lobe forming a specialised water-holding pocket called a water-sac. The plant shows seasonal colour variation from rose to purple to brown to spring green, developing reddish-purple pigmentation in autumn and winter. It reproduces both sexually, through spores produced in reddish-brown capsules, and asexually via single-celled gemmae. N. curvifolia serves as an indicator species in forest ecosystems, particularly in montane spruce-fir forests, where it often forms pure mats on decorticated logs and is associated with the slime mould species Barbeyella minutissima.
