|
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] |
Georg Heinrich Mettenius
Georg Heinrich Mettenius (24 November 1823 – 18 August 1866) was a German botanist born in Frankfurt am Main. He was son-in-law to botanist Alexander Braun (1805–1877). In 1845 he received his medical doctorate from the University of Heidelberg. After graduation, he studied marine algae in Helgoland and Fiume. In 1848 he returned to Heidelberg as a privat-docent, and was later appointed an associate professor of botany at Freiburg. In 1852 he became a full professor at the University of Leipzig as well as director of its botanical garden. He died of cholera in Leipzig at the age of 42. Mettenius was a leading authority in the field of pteridology. The plant genus '' Metteniusa'' (family Metteniusaceae) is named in his honor. Selected publications * ''Beiträge zur Kenntniss der Rhizocarpeen'' (1846) - Contributions to the knowledge of Rhizocarpaceae. * "Filices horti botanici Lipsiensis" (1856) * "Filices Lechlerianae Chilenses ac Peruanae cura" (1856). * ''Über einig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tripinnate
Pinnation (also called pennation) is the arrangement of feather-like or multi-divided features arising from both sides of a common axis. Pinnation occurs in biological morphology, in crystals, such as some forms of ice or metal crystals, and in patterns of erosion or stream beds. The term derives from the Latin word ''pinna'' meaning "feather", "wing", or "fin". A similar concept is "pectination," which is a comb-like arrangement of parts (arising from one side of an axis only). Pinnation is commonly referred to in contrast to "palmation," in which the parts or structures radiate out from a common point. The terms "pinnation" and "pennation" are cognate, and although they are sometimes used distinctly, there is no consistent difference in the meaning or usage of the two words.Jackson, Benjamin, Daydon; A Glossary of Botanic Terms with their Derivation and Accent; Published by Gerald Duckworth & Co. London, 4th ed 1928 Plants Botanically, pinnation is an arrangement of discr ... [...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 Lumholtzii
''Argyrochosma lumholtzii'' is a rare fern in the family Pteridaceae known from Sonora, Mexico. It is quite similar to Jones' false cloak fern, but has black leaf axes and a less highly divided leaf. First described as a species in 1939, honoring the explorer Carl Sofus Lumholtz, 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 lumholtzii'' is a small fern. The rhizome is compact and upright. It bears linear or linear-ligulate (straplike) scales long, long-acuminate at the tip, somewhat twisted, of a uniform orange-brown or reddish-brown color, with entire (toothless) margins. From it, the fronds arise in clumps. From base to tip of leaf, they are long. Of this length, about two-thirds is made up by the stipe (the stalk of the leaf, below the blade), which is shiny and round, hairless, and black in color. The leaf blades ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Argyrochosma Jonesii
''Argyrochosma jonesii'', known as Jones' false cloak fern, is a species of fern native to the southwestern United States and Sonora, Mexico. It grows on calcareous rocks, and has small, finely-divided leaves with a leathery texture and dark axes connecting the leaf segments. Unlike many members of ''Argyrochosma'', it does not secrete white powder on the underside of its leaves. First described as a species in 1917, 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 linear or linear-subulate, uniformly colored, brown or reddish-brown scales, sometimes nearly black in color, with entire (toothless) margins and a thin texture. They are long and wide. The leaves range from long, and arise in clumps. The stipe (the stalk of the leaf, below the blade) is chestnut brown ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
Argyrochosma Fendleri
''Argyrochosma fendleri'', Fendler's false cloak fern, is a fern known from the western United States and northwestern Mexico. It grows in rocky habitats, and is distinguished from other members of the genus by its zig-zag leaf axes. Like many species in the genus, it bears white powder on the underside of its leaves. First described as a species in 1851, 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 fendleri'' is a medium-sized epipetric fern. The rhizome is compact, wide, and may be horizontal or upright. It bears linear to lanceolate scales long, thin in texture and of a uniform orange-brown or chestnut-brown color with entire (toothless) margins. From it, numerous fronds arise in dense clumps. From base to tip of leaf, they are long and wide. Of this length, about half is made up by the stipe (the stalk of the leaf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Argyrochosma Microphylla Leaf Underside
''Argyrochosma'' is a genus of ferns known commonly as false cloak ferns. The genus is included in the Cheilanthoideae subfamily of the Pteridaceae. Species now in this genus were previously treated as members of related genera ''Notholaena'' or ''Pellaea'' but were segregated into their own genus in 1987. These ferns, of which there are about 20 species, are mostly native to the Americas, from North to South and including the Caribbean, while one species, ''A. connectens'', is known from Sichuan, China. They are commonly found growing in cracks between rocks. Their leaves are generally shorter than 40 centimeters and have rounded bluish or grayish green segments. Often the lower surface of the segments is coated in a white dust, and the sporangia contain brown spores. Species , the ''Checklist of Ferns and Lycophytes of the World'' recognized the following species: *''Argyrochosma chilensis'' (Fée ex J.Rémy) Windham *'' Argyrochosma connectens'' (C.Chr.) G.M.Zhang *''Argy ... [...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] |
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 ... [...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 re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glaucous
''Glaucous'' (, ) is used to describe the pale grey or bluish-green appearance of the surfaces of some plants, as well as in the names of birds, such as the glaucous gull (''Larus hyperboreus''), glaucous-winged gull (''Larus glaucescens''), glaucous macaw (''Anodorhynchus glaucus''), and glaucous tanager (''Thraupis glaucocolpa''). The term ''glaucous'' is also used botanically as an adjective to mean "covered with a greyish, bluish, or whitish waxy coating or bloom that is easily rubbed off" (e.g. glaucous leaves). The first recorded use of ''glaucous'' as a color name in English was in the year 1671. Examples The epicuticular wax coating on mature plum fruit gives them a glaucous appearance. Another familiar example is found in the common grape genus (''Vitis vinifera''). Some cacti have a glaucous coating on their stem(s). Glaucous coatings are hydrophobic so as to prevent wetting by rain. Their waxy character serves to hinder climbing of leaves, stem or fruit by inse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
