| Lejeunea mandonii | |
|---|---|
Scientific classification  | |
| Kingdom: | Plantae |
| Division: | Marchantiophyta |
| Class: | Jungermanniopsida |
| Order: | Porellales |
| Family: | Lejeuneaceae |
| Genus: | Lejeunea |
| Species: | L. mandonii |
| Binomial name | |
| Lejeunea mandonii (Steph.) Müll. Frib. | |
Lejeunea mandonii, also known as Atlantic lejeunea [2] is a species of liverwort from the Lejeuneaceae family. [3]
Lejeunea mandonii is a very small, leafy liverwort. Its leaves are incubous and exhibit both shades of green and yellow. [4] Stems of L. mandonii are usually less than 10mm long. [5] L. mandonii is the only British member of the genus Lejeunea that possesses smooth and cylindrical perianths. [6]
Lejeunea mandonii is endemic to Europe where it can be found within the following countries and territories: United Kingdom, Ireland, Portugal, Canary Islands and Madeira. [4]
Within the United Kingdom it can be found in a few sites located in Western Scotland and the Lizard Peninsula of Western Cornwall. [5] The distribution within the UK is restricted to Atlantic Coastal regions. [4]
This species can be found in sheltered and shaded woodlands where it grows among other species of liverworts and mosses. [4]
Lejeunea mandonii can also be found growing on rocky overhands, ravines and north facing cliffs near to the coast. [4]
It has also been recorded growing on the bark and trunks of trees. [4]
Lejeunea mandonii is a rare species, [5] which has populations persisting in fragmented locations. [4] Habitat fragmentation causes populations to be isolated and therefore inbreeding and a loss of genetic diversity can occur. This can cause a species to be more at risk of extinction. [7]
The species is also under threat from being shaded out by both native and introduced plant species. Heavy shade can be detrimental to L. mandonii populations. [5] Non-native evergreen tree species such as the Western Red Cedar Thuja plicata when planted in proximity to L. mandonii causes heavy shade. Deciduous tree species such as the native Sycamore Acer pseudoplatanus if allowed to mature can also be responsible for shading out L. mandonii. [5]
Invasive species such as the shrub Rhododendron ponticum can also harm L. mandonii populations. Regular human intervention is needed to cut back the shrub so that it does not shade out rocky habitat where Lejeunea mandonii grows. [5]
All three current known populations of L. mandonii in Scotland are isolated, growing on three different individual Ash trees Fraxinus excelsior . [6] [5] Due to the arrival of the fungi Hymenoscyphus fraxineus within the United Kingdom, they are threatened by Ash dieback disease. [8] If these trees were to succumb to ash dieback, L. mandonii could lose further habitat.
Due to populations of L. mandonii usually being found in small patches of habitat. Its rarity and vulnerability can put it at risk of poaching by bryologists. [9]
Fraxinus, commonly called ash, is a genus of plants in the olive and lilac family, Oleaceae, and comprises 45–65 species of usually medium-to-large trees, most of which are deciduous trees, although some subtropical species are evergreen trees. The genus is widespread throughout much of Europe, Asia, and North America.
Fraxinus americana, the white ash or American ash, is a fast-growing species of ash tree native to eastern and central North America.
Fraxinus excelsior, known as the ash, or European ash or common ash to distinguish it from other types of ash, is a flowering plant species in the olive family Oleaceae. It is native throughout mainland Europe east to the Caucasus and Alborz mountains, and Great Britain and Ireland, the latter determining its western boundary. The northernmost location is in the Trondheimsfjord region of Norway. The species is widely cultivated and reportedly naturalised in New Zealand and in scattered locales in the United States and Canada.
Habitat fragmentation describes the emergence of discontinuities (fragmentation) in an organism's preferred environment (habitat), causing population fragmentation and ecosystem decay. Causes of habitat fragmentation include geological processes that slowly alter the layout of the physical environment, and human activity such as land conversion, which can alter the environment much faster and causes the extinction of many species. More specifically, habitat fragmentation is a process by which large and contiguous habitats get divided into smaller, isolated patches of habitats.
Habitat destruction occurs when a natural habitat is no longer able to support its native species. The organisms once living there have either moved to elsewhere or are dead, leading to a decrease in biodiversity and species numbers. Habitat destruction is in fact the leading cause of biodiversity loss and species extinction worldwide.
Lunularia is a genus of liverworts whose only species is Lunularia cruciata, the crescent-cup liverwort. Lunularia is either the only genus in the order Lunulariales, or may be placed in the order Marchantiales. The name, from Latin luna, moon, refers to the moon-shaped gemma cups.
Hypoxylon is a genus of ascomycetes commonly found on dead wood, and usually one of the earliest species to colonise dead wood. A common European species is Hypoxylon fragiforme which is particular common on dead trunks of beech.
Plantlife is a wild plant conservation charity. As of 2023, it manages 24 nature reserves around the United Kingdom. HM King Charles III is patron of the charity.
The pink-legged graveteiro is a species of bird in the family Furnariidae that is endemic to the Atlantic Forest located in the southeast part of Brazil, thriving in local cocoa plantations. As of 2000 the pink-legged graveteiro is listed as a vulnerable species. The estimated population of the pink-legged graveteiro is between 2,500 and 9,999 individuals left in the wild. Its main habitat is cocoa plantations. It is the only member of the genus Acrobatornis.
Fraxinus profunda, the pumpkin ash, is a species of ash (Fraxinus) native to eastern North America, where it has a scattered distribution on the Atlantic coastal plain and interior lowland river valleys from the Lake Erie basin in Ontario and New York west to Illinois, southwest to Missouri and southeast to northern Florida. It grows in bottomland habitats, such as swamps, floodplains and riverbanks. It is threatened by the emerald ash borer, an invasive insect which has caused widespread destruction of ash trees in eastern North America.
Cornwall is the county that forms the tip of the southwestern peninsula of England; this area has a mild and warm climate regulated by the Gulf Stream. The mild climate allows rich plant cover, such as palm trees in the far south and west of the county and in the Isles of Scilly, due to sub-tropical conditions in the summer.
Forest dieback is a condition in trees or woody plants in which peripheral parts are killed, either by pathogens, parasites or conditions like acid rain, drought, and more. These episodes can have disastrous consequences such as reduced resiliency of the ecosystem, disappearing important symbiotic relationships and thresholds. Some tipping points for major climate change forecast in the next century are directly related to forest diebacks.
Forest pathology is the research of both biotic and abiotic maladies affecting the health of a forest ecosystem, primarily fungal pathogens and their insect vectors. It is a subfield of forestry and plant pathology.
Important Plant Areas (IPA) is a programme set up in the UK, by the organisation Plantlife, to provide a framework for identifying and maintaining the richest sites for plant life, possibly within existing protected areas; though the protection of the IPA itself is not legally enforced. The term plant life in this case refers to any number of species, encompassing algae, fungi, lichens, liverworts, mosses, and wild vascular plants. IPAs are selected with the intention of focusing on the conservation of the important wild plant populations in these areas, and act as a subset in the broader context of Key Biodiversity Areas. Designating an IPA is intended to gain awareness and encourage long-term conservation through an 'ecosystem-based' approach.
Hymenoscyphus fraxineus is an ascomycete fungus that causes ash dieback, a chronic fungal disease of ash trees in Europe characterised by leaf loss and crown dieback in infected trees. The fungus was first scientifically described in 2006 under the name Chalara fraxinea. Four years later it was discovered that Chalara fraxinea is the asexual (anamorphic) stage of a fungus that was subsequently named Hymenoscyphus pseudoalbidus and then renamed as Hymenoscyphus fraxineus.
Hymenoscyphus albidus is a saprotrophic fungus which grows on the dead leaves of ash trees.
The Future Trees Trust is a charity that aims to improve and increase the stock of hardwood trees in Britain and Ireland.
Celtic Rainforest is a colloquial term which refers to the temperate rainforest of Ireland and Great Britain. These woodlands are also variously referred to as Atlantic rainforest, Upland Oakwoods, Atlantic Oakwoods or Western Oakwoods. Today, the Celtic Rainforest exists as small fragments of the temperate rainforest that once covered much of Ireland and the west coast of Great Britain. The majority of these fragments occur on steep-sided slopes above rivers and lakes which have avoided clearance and intensive grazing pressure. There are notable examples in Ireland especially along its western coast, including the Beara Rainforest in West Cork, the Great Forest of Aughty in Clare and Galway, Oldhead Wood in Mayo and Ardnamona Wood and Glenveagh in Donegal. In Scotland, rainforest exists on the islands and shores of Loch Maree, Loch Sunart, Loch Lomond, and one of the best preserved sites on the remote Taynish Peninsula in Argyll. In Wales, they occur on steep-sided riverine gorges in Snowdonia and Mid Wales. In England, there are examples in the Lake District, and steep-sided riverine and estuarine valleys in South West England, including the Fowey valley in Cornwall, and the valley of the river Dart which flows off Dartmoor, and has rainfall in excess of 2 metres per year.
Anne Edwards is a British plant scientist, based at the John Innes Centre and was the first person in the UK to identify Ash dieback disease in England,
Fraxinus paxiana is a species of flowering plant in the family Oleaceae, native to central and southern China. A tree reaching 20 m (66 ft), it is found in forested valley slopes, usually from 400 to 1,100 m above sea level. In the wild it is heavily infected with Hymenoscyphus fraxineus, the fungal pathogen that causes ash dieback, but shows little damage.
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