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Argyrochosma Formosa
''Argyrochosma formosa'' is a fern known from eastern and central Mexico and Guatemala. It grows on rocky slopes, particularly on limestone. Unlike many members of the genus, it lacks white powder on the underside of its leaves. First described as a species in 1842, it was transferred to the new genus ''Argyrochosma'' (the "false cloak ferns") in 1987, recognizing their distinctness from the "cloak ferns" (''Notholaena'' ''sensu stricto''). Description ''Argyrochosma formosa'' is a medium-sized epipetric fern. The rhizome is compact and horizontal. It bears linear scales or long and wide, hair-tipped and with entire (toothless) margins. They range from tan to dark orange or rusty in color and feel oily-viscid. From the rhizome, the fronds arise in clumps. The fronds are from about long, sometimes as short as , and broad. Of their length, about 25% to 50% is made up by the stipe (the stalk of the leaf, below the blade), which is shiny or sometimes glaucous and round, hairless ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frederik Liebmann
Frederik Michael Liebmann (10 October 1813 – 29 October 1856) was a Danish botanist. Liebmann studied botany at the University of Copenhagen, although he never obtained a formal qualification. He went on study tours of Germany and Norway before becoming lecturer at the Danish Royal Veterinary School in 1837. In 1840 he travelled to Cuba and Mexico; on his return in 1845 he was appointed Professor of Botany at the University of Copenhagen. He became Director of the university's Botanical Garden in 1852, a post he held until his death four years later. He was the editor of Flora Danica ''Flora Danica'' is a comprehensive atlas of botany from the Age of Enlightenment, containing folio-sized pictures of all the wild plants native to Denmark, in the period from 1761 to 1883. History ''Flora Danica'' was proposed by G. C. Oede ... and issued fasc. 41-43 (1845–1852) and Supplement vol. 1, a total of 240 plates. Legacy Liebmann is commemorated in the scientific name of a specie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glossary Of Leaf Morphology
The following is a list of terms which are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (a single leaf blade or lamina) or compound (with several leaflets). The edge of the leaf may be regular or irregular, may be smooth or bearing hair, bristles or spines. For more terms describing other aspects of leaves besides their overall morphology see the leaf article. The terms listed here all are supported by technical and professional usage, but they cannot be represented as mandatory or undebatable; readers must use their judgement. Authors often use terms arbitrarily, or coin them to taste, possibly in ignorance of established terms, and it is not always clear whether because of ignorance, or personal preference, or because usages change with time or context, or because of variation between specimens, even specimens from the same plant. For example, whether to call leaves on the same tree "acuminate", "lanceolate", or "linear" could ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carl Borivoj Presl
Carl Borivoj Presl ( cs, Karel Bořivoj Presl; 17 February 1794 – 2 October 1852) was a Czech botanist. Biography Presl lived his entire life in Prague, and was a professor of botany at the University of Prague (1833–52).BHL Taxonomic literature : a selective guide to botanical publications He made an expedition to in 1817, and with his brother, published a "Flora bohemica" titled "''Flora čechica: indicatis medicinalibus, oeconomicis technologicisque plantis''" in 1819. His older brother was also a noted botanist; the journal '' |
Cheilanthes Pulchella
''Cheilanthes'', commonly known as lip ferns, is a genus of about 180 species of rock-dwelling ferns with a cosmopolitan distribution in warm, dry, rocky regions, often growing in small crevices high up on cliffs. Most are small, sturdy and evergreen. The leaves, often densely covered in trichomes, spring directly from the rootstocks. Many of them are desert ferns, curling up during dry times and reviving with the coming of moisture. At the ends of veins sporangia, or spore-bearing structures, are protected by leaf margins, which curl over them. Taxonomy The genus name is derived from the Greek words χεῖλος (''cheilos''), meaning "lip," and ἄνθος (''anthos''), meaning "flower." ''Cheilanthes'' as traditionally circumscribed is now known to be highly paraphyletic, comprising at least four generically separate groups. The type species, '' C. micropteris'', is most closely allied to the genera ''Aleuritopteris'' and ''Sinopteris'' (Schuettpelz ''et al.''). In t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species Description
A species description is a formal description of a newly discovered species, usually in the form of a scientific paper. Its purpose is to give a clear description of a new species of organism and explain how it differs from species that have been described previously or are related. In order for species to be validly described, they need to follow guidelines established over time. Zoological naming requires adherence to the ICZN code, plants, the ICN, viruses ICTV, and so on. The species description often contains photographs or other illustrations of type material along with a note on where they are deposited. The publication in which the species is described gives the new species a formal scientific name. Some 1.9 million species have been identified and described, out of some 8.7 million that may actually exist. Millions more have become extinct throughout the existence of life on Earth. Naming process A name of a new species becomes valid (available in zo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Argyrochosma Microphylla
''Argyrochosma microphylla'', the small-leaf false cloak fern, is a species of fern native to New Mexico, Texas and northern Mexico. It grows on limestone rocks and cliffs, and has finely-divided leaves with small leaf segments, often folded in half when dry, which lack the white powder present on the leaf underside of many related species. First described as a species in 1869, it was transferred to the new genus ''Argyrochosma'' (the "false cloak ferns") in 1987, recognizing their distinctness from the "cloak ferns" (''Notholaena'' ''sensu stricto''). Description The rhizome is short and horizontal, with leaves closely spaced. It bears thin, narrowly lanceolate or linear brown to dark orange, chestnut-brown, or reddish-brown scales , of a uniform color and with entire (toothless) margins. The leaves are long, arising in clumps. The stipe (the stalk of the leaf, below the blade) is rounded, somewhat flattened or grooved on the upper surface, reddish-brown to dark brown, or che ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Argyrochosma Incana
''Argyrochosma incana'', the hairy false cloak fern, is a fern known from the southwestern United States through Mexico to Guatemala, and from a disjunct population in the Dominican Republic. It grows on rocky slopes and steep banks, often in forests. Like many of the false cloak ferns, it bears white powder on the underside of its leaves. First described as a species in 1825, it was transferred to the new genus ''Argyrochosma'' (the "false cloak ferns") in 1987, recognizing their distinctness from the "cloak ferns" (''Notholaena'' ''sensu stricto''). Description ''Argyrochosma incana'' is a medium-sized epipetric fern. The rhizome is short, thick, and may be horizontal or somewhat upright. It bears linear to lanceolate or linear-ligulate (straplike) scales long and wide, without teeth at the margins and long-attenuate at the tip. They are of a uniform dark, shiny brown, chestnut-brown or yellowish-brown color with some dark brown patches. From the rhizome, the fronds arise in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apomictic
In botany, apomixis is asexual reproduction without fertilization. Its etymology is Greek for "away from" + "mixing". This definition notably does not mention meiosis. Thus "normal asexual reproduction" of plants, such as propagation from cuttings or leaves, has never been considered to be apomixis, but replacement of the seed by a plantlet or replacement of the flower by bulbils were categorized as types of apomixis. Apomictically produced offspring are genetically identical to the parent plant. Some authors included all forms of asexual reproduction within apomixis, but that generalization of the term has since died out. In flowering plants, the term "apomixis" is commonly used in a restricted sense to mean agamospermy, i.e., clonal reproduction through seeds. Although agamospermy could theoretically occur in gymnosperms, it appears to be absent in that group. Apogamy is a related term that has had various meanings over time. In plants with independent gametophytes (notab ... [...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 meiospores. 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, arrangemen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sorus
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 meiospores. 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, arrangem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epicuticular Wax
Epicuticular wax is a coating of wax covering the outer surface of the plant cuticle in land plants. It may form a whitish film or bloom on leaves, fruits and other plant organs. Chemically, it consists of hydrophobic organic compounds, mainly straight-chain aliphatic hydrocarbons with or without a variety of substituted functional groups. The main functions of the epicuticular wax are to decrease surface wetting and moisture loss. Other functions include reflection of ultraviolet light, assisting in the formation of an ultra-hydrophobic and self-cleaning surface and acting as an anti-climb surface. Chemical composition Common constituents of epicuticular wax are predominantly straight-chain aliphatic hydrocarbons that may be saturated or unsaturated and contain a variety of functional groups. These waxes can be composed of a variety of compounds which differ between plant species. Paraffins occur in leaves of peas and cabbages. Leaves of carnauba palm and banana feature alky ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rachis
In biology, a rachis (from the grc, ῥάχις [], "backbone, spine") is a main axis or "shaft". In zoology and microbiology In vertebrates, ''rachis'' can refer to the series of articulated vertebrae, which encase the spinal cord. In this case the ''rachis'' usually forms the supporting axis of the body and is then called the spine or vertebral column. ''Rachis'' can also mean the central shaft of pennaceous feathers. In the gonad of the invertebrate nematode ''Caenorhabditis elegans'', a rachis is the central cell-free core or axis of the gonadal arm of both adult males and hermaphrodites where the germ cells have achieved pachytene and are attached to the walls of the gonadal tube. The rachis is filled with cytoplasm. In botany In plants, a rachis is the main axis of a compound structure. It can be the main stem of a compound leaf, such as in ''Acacia'' or ferns, or the main, flower-bearing portion of an inflorescence above a supporting peduncle. Where it subdivide ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
