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Asplenium Montanum
''Asplenium montanum'', commonly known as the mountain spleenwort, is a small fern endemic to the eastern United States. It is found primarily in the Appalachian Mountains from Vermont to Alabama, with a few isolated populations in the Ozarks and in the Ohio Valley. It grows in small crevices in sandstone cliffs with highly acid soil, where it is usually the only vascular plant occupying that ecological niche. It can be recognized by its tufts of dark blue-green, highly divided leaves. The species was first described in 1810 by the botanist Carl Ludwig Willdenow. No subspecies have been described, although a discolored and highly dissected form was reported from the Shawangunk Mountains in 1974. ''Asplenium montanum'' is a diploid member of the "Appalachian ''Asplenium'' complex," a group of spleenwort species and hybrids which have formed by reticulate evolution. Members of the complex descended from ''A. montanum'' are among the few other vascular plants that can tol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carl Ludwig Willdenow
Carl Ludwig Willdenow (22 August 1765 – 10 July 1812) was a German botanist, pharmacist, and plant taxonomist. He is considered one of the founders of phytogeography, the study of the geographic distribution of plants. Willdenow was also a mentor of Alexander von Humboldt, one of the earliest and best known phytogeographers. He also influenced Christian Konrad Sprengel, who pioneered the study of plant pollination and floral biology. Biography Willdenow was born in Berlin and studied medicine and botany at the University of Halle. After studying pharmaceutics at Wieglieb College, Langensalza and in medicine at Halle, he returned to Berlin to work at his father's pharmacy located in the Unter den Linden. His early interest in botany was kindled by his uncle J. G. Gleditsch and he started a herbarium collection in his teenage years. In 1794 he became a member of the Berlin Academy of Sciences. He was a director of the Botanical garden of Berlin from 1801 until his death. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stipe (botany)
In botany, a stipe is a stalk that supports some other structure. The precise meaning is different depending on which taxonomic group is being described. file:Helicteres-Yucatán-Flowers.jpg, The long stipe of a '' Helicteres'' flower. file:Helicteres-Yucatán-Fruits.jpg, remains as each flower forms a fruit. In the case of ferns, the stipe is only the petiole from the rootstock to the beginning of the leaf tissue, or lamina. The continuation of the structure within the lamina is then termed a rachis. In flowering plants, the term is often used in reference to a stalk that sometimes supports a flower's ovary. In orchids, the stipe or caudicle is the stalk-like support of the pollinia. It is a non-viscid band or strap connecting the pollinia with the viscidium (the viscid part of the rostellum or beak). A stipe is also a structure found in organisms that are studied by botanists but that are no longer classified as plants. It may be the stem-like part of the thallus of a mus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Athyrium
''Athyrium'' (lady-fern) is a genus of about 180 species of terrestrial ferns, with a cosmopolitan distribution. It is placed in the family Athyriaceae, in the order Polypodiales. Its genus name is from Greek '' a-'' ('without') and Latinized Greek ''thyreos'' ('shield'), describing its inconspicuous indusium (sorus' covering). The common name "lady fern" refers in particular to the common lady fern, ''Athyrium filix-femina''.Entry "lady fern", ''New Oxford American Dictionary 3rd edition'' (2010) by Oxford University Press, Inc. ''Athyrium'' species are used as food plants by the larvae of some Lepidoptera species including the small angle shades and ''Sthenopis auratus ''Sthenopis pretiosus'', the gold-spotted ghost moth, is a species of moth of the family Hepialidae. It was first described by Gottlieb August Wilhelm Herrich-Schäffer in 1856. It can be found in found Brazil, Venezuela and in the eastern United ...''. Species There are about 180, including: References ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asplenium Adiantum-nigrum
''Asplenium adiantum-nigrum'' is a common species of fern known by the common name black spleenwort. It is found mostly in Africa, Europe, and Eurasia, but is also native to a few locales in Mexico and the United States. Description This spleenwort has thick, triangular leaf blades up to 10 centimeters long which are divided into several subdivided segments. It is borne on a reddish green petiole and the rachis is shiny and slightly hairy. The undersides of each leaf segment have one or more sori arranged in chains.Esser, Lora L. 1994''Asplenium adiantum-nigrum''.In: Fire Effects Information System, nline U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Taxonomy Linnaeus was the first to describe black spleenwort with the binomial ''Asplenium adiantum-nigrum'' in his '' Species Plantarum'' of 1753. A chloroplast phylogeny verified the allopolyploid origin of ''A. adiantum-nigrum'', with '' A. cu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
André Michaux
André Michaux, also styled Andrew Michaud, (8 March 174611 October 1802) was a French botanist and explorer. He is most noted for his study of North American flora. In addition Michaux collected specimens in England, Spain, France, and even Persia. His work was part of a larger European effort to gather knowledge about the natural world. Michaux's contributions include ''Histoire des chênes de l'Amérique'' (1801; "The Oaks of North America") and ''Flora Boreali-Americana'' (1803; "The Flora of North America") which continued to be botanical references well into the 19th century. His son, François André Michaux, also became an authoritative botanist. Biography Michaux was born in Satory, part of Versailles, Yvelines, where his father managed farmland on the king's estate. Michaux was trained in the agricultural sciences in anticipation of his one-day assuming his father's duties, and received a basic classical 18th century education, including Latin and some Greek, until h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asplenium × Wherryi
''Asplenium'' × ''wherryi'', known as Wherry's spleenwort, is a rare hybrid fern of the Appalachian Mountains. The sterile triploid offspring of mountain spleenwort ( ''A. montanum'') and Bradley's spleenwort ( ''A. bradleyi''), it is known from a few sites where those species grow together. First collected by Edgar T. Wherry in 1935, it was largely ignored until a new colony was found in 1961, and the species was named in his honor. Description ''Asplenium'' × ''wherryi'' is a small, evergreen fern. The fronds are monomorphic, showing little or no difference between sterile and fertile fronds. The dark-colored stipe (the stalk of the leaf, below the blade) is up to long, while the rachis (the central axis of the leaf) is green. The leaf blades are lance-shaped, cut into ten to sixteen pairs of pinnae. The leaf blades are bipinnate at the base (with pinnae fully cut into pinnules), becoming pinnate-pinnatifid (with lobed pinnae) in the middle of the blade and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asplenium Ruta-muraria
''Asplenium ruta-muraria'' is a species of fern commonly known as wall-rue (but which, as a fern, is not by any means closely related to common rue). It is a very small epipetric species, growing exclusively on limestone and other calcareous rocks. Its fronds are bluish-green and are heavily sub-divided, becoming up to 12 cm in length. Taxonomy Linnaeus first gave wall-rue the binomial ''Asplenium ruta-muraria'' in his '' Species Plantarum'' of 1753. A global phylogeny of ''Asplenium'' published in 2020 divided the genus into eleven clades, which were given informal names pending further taxonomic study. ''A. ruta-muraria'' belongs to the "''Pleurosorus'' subclade" of the "''Pleurosorus'' clade". The ''Pleurosorus'' clade has a worldwide distribution; members are generally small and occur on hillsides, often sheltering among rocks in exposed habitats. ''A. ruta-muraria'' is exceptional within the subclade for its lack of hairs on the leaf. The phylogeny suggests t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asplenium Bradleyi
''Asplenium bradleyi'', commonly known as Bradley's spleenwort or cliff spleenwort, is a rare epipetric fern of east-central North America. Named after Professor Frank Howe Bradley, who first collected it in Tennessee, it may be found infrequently throughout much of the Appalachian Mountains, the Ozarks, and the Ouachita Mountains, growing in small crevices on exposed sandstone cliffs. The species originated as a hybrid between mountain spleenwort (''Asplenium montanum'') and ebony spleenwort (''Asplenium platyneuron''); ''A. bradleyi'' originated when that sterile diploid hybrid underwent chromosome doubling to become a fertile tetraploid, a phenomenon known as allopolyploidy. Studies indicate that the present population of Bradley's spleenwort arose from several independent doublings of sterile diploid hybrids. ''A. bradleyi'' can also form sterile hybrids with several other spleenworts. While ''A. bradleyi'' is easily outcompeted by other plants in more ferti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sporophyte
A sporophyte () is the diploid multicellular stage in the life cycle of a plant or alga which produces asexual spores. This stage alternates with a multicellular haploid gametophyte phase. Life cycle The sporophyte develops from the zygote produced when a haploid egg cell is fertilized by a haploid sperm and each sporophyte cell therefore has a double set of chromosomes, one set from each parent. All land plants, and most multicellular algae, have life cycles in which a multicellular diploid sporophyte phase alternates with a multicellular haploid gametophyte phase. In the seed plants, the largest groups of which are the gymnosperms and flowering plants (angiosperms), the sporophyte phase is more prominent than the gametophyte, and is the familiar green plant with its roots, stem, leaves and cones or flowers. In flowering plants the gametophytes are very reduced in size, and are represented by the germinated pollen and the embryo sac. The sporophyte produces spores (hence t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spore
In biology, a spore is a unit of sexual or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plants, algae, fungi and protozoa. Bacterial spores are not part of a sexual cycle, but are resistant structures used for survival under unfavourable conditions. Myxozoan spores release amoeboid infectious germs ("amoebulae") into their hosts for parasitic infection, but also reproduce within the hosts through the pairing of two nuclei within the plasmodium, which develops from the amoebula. In plants, spores are usually haploid and unicellular and are produced by meiosis in the sporangium of a diploid sporophyte. Under favourable conditions the spore can develop into a new organism using mitotic division, producing a multicellular gametophyte, which eventually goes on to produce gametes. Two gametes fuse to form a zygote which develops into a new s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sporangium
A sporangium (; from Late Latin, ) is an enclosure in which spores are formed. It can be composed of a single cell or can be multicellular. Virtually all plants, fungi, and many other lineages form sporangia at some point in their life cycle. Sporangia can produce spores by mitosis, but in nearly all land plants and many fungi, sporangia are the site of meiosis and produce genetically distinct haploid spores. Fungi In some phyla of fungi, the sporangium plays a role in asexual reproduction, and may play an indirect role in sexual reproduction. The sporangium forms on the sporangiophore and contains haploid nuclei and cytoplasm. Spores are formed in the sporangiophore by encasing each haploid nucleus and cytoplasm in a tough outer membrane. During asexual reproduction, these spores are dispersed via wind and germinate into haploid hyphae. Although sexual reproduction in fungi varies between phyla, for some fungi the sporangium plays an indirect role in sexual reprod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indusium
A sorus (pl. sori) is a cluster of sporangia (structures producing and containing spores) in ferns and fungi. A coenosorus (plural coenosori) is a compound sorus composed of multiple, fused sori. Etymology This New Latin word is from Ancient Greek σωρός (''sōrós'' 'stack, pile, heap'). Structure In lichens and other fungi, the sorus is surrounded by an external layer. In some red algae, it may take the form of depression into the thallus. In ferns, the sori form a yellowish or brownish mass on the edge or underside of a fertile frond. In some species, they are protected during development by a scale or film of tissue called the indusium, which forms an umbrella-like cover. Lifecycle significance Sori occur on the sporophyte generation, the sporangia within producing haploid meio spores. As the sporangia mature, the indusium shrivels so that spore release is unimpeded. The sporangia then burst and release the spores. As an aid to identification The shape, arran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
