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Myriopteris Gracillima IMG 3892 Crop
''Myriopteris'', commonly known as the lip ferns, is a genus of cheilanthoid ferns. Like other cheilanthoids, they are ferns of dry habitats, reproducing both sexually and apogamously. Many species have leaves divided into a large number of small, bead-like segments, the probable inspiration for the generic name. Hairs and/or scales are often present on both the upper and lower surfaces of the leaf, and their presence and appearance are useful in distinguishing between species. The genus is most diverse in Mexico, but species are found from southwestern Canada south to southern Chile, and one species is endemic to southern Africa. Description No single morphological character divides ''Myriopteris'', as presently circumscribed, from the other cheilanthoids. Convergent evolution in arid environments is thought to be responsible for widespread homoplasy in the morphological characters traditionally used to classify this group. While small, bead-like ultimate segments are associate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myriopteris Wootonii
''Myriopteris wootonii'', formerly known as ''Cheilanthes wootonii'', is a species of fern in the Pteridaceae family (subfamily Cheilanthoideae) with the common name Wooton's lace fern. Description ''Myriopteris wootonii'' grows fronds from a long creeping rhizome with tan to brown scales. The frond (leaf) is 10-20 cm long and 2-3 cm wide with a narrow stem (stipe) 1-2 mm thick. The leaf blade 3 to 4-pinnate and the leaflets are small and nearly round. Their abaxial (lower) surface is concave and densely covered with cilia and lanceolate-linear scales, and their adaxial (top) surface is glabrous. The leaf viewed from above has the general appearance of a flat array of tiny green pebbles, an appearance that is shared by several other ''Myriopteris ''Myriopteris'', commonly known as the lip ferns, is a genus of cheilanthoid ferns. Like other cheilanthoids, they are ferns of dry habitats, reproducing both sexually and apogamously. Many species have leaves divided into a large ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indumentum
In biology, an indumentum (Latin, literally: "garment") is a covering of trichomes (fine "hairs") on a plant Davis, Peter Hadland and Heywood, Vernon Hilton (1963) ''Principles of angiosperm taxonomy'' Van Nostrandpage, Princeton, New Jersey, page 154, or of bristles (rarely scales) of an insect. In plants, indumentum types include: *pubescent *hirsute *pilose *lanate *villous *tomentose *stellate *scabrous *scurfy The indumentum on plants can have a wide variety of functions, including as anchorage in climbing plants (e.g., ''Galium aparine''), in transpiration control, in water absorption (''Tillandsia''), the reflection of solar radiation, increasing water-repellency (e.g., in the aquatic fern ''Salvinia''), in protection against insect predation, and in the trapping of insects (''Drosera'', ''Nepenthes'', ''Stylosanthes''). The use of an indumentum on insects can also be pollen-related, as on bees, sensory like whiskers, or for varied other uses including adhesion an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Michael D
Michael D may refer to: * Mike D (born 1965), founding member of the Beastie Boys Arts * Michael D. Cohen (actor) (born 1975), Canadian actor * Michael D. Ellison, African American recording artist * Michael D. Fay, American war artist * Michael D. Ford (1928–2018), English set decorator * Michael D. Roberts, American actor Business * Michael D. Dingman (1931–2017), American businessman * Michael D. Ercolino (1906–1982), American businessman * Michael D. Fascitelli, (born c. 1957), American businessman * Michael D. Penner (born 1969), Canadian lawyer and businessman Education * Michael D. Aeschliman (born 1948), American–Swiss educator * Michael D. Cohen (academic) (1945–2013), professor of complex systems, information and public policy at the University of Michigan * Michael D. Hanes, American music educator * Michael D. Hurley (born 1976), British Professor of Literature and Theology * Michael D. Johnson, a former President of John Carroll University * Mic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Convergent Evolution
Convergent evolution is the independent evolution of similar features in species of different periods or epochs in time. Convergent evolution creates analogous structures that have similar form or function but were not present in the last common ancestor of those groups. The cladistic term for the same phenomenon is homoplasy. The recurrent evolution of flight is a classic example, as flying insects, birds, pterosaurs, and bats have independently evolved the useful capacity of flight. Functionally similar features that have arisen through convergent evolution are ''analogous'', whereas '' homologous'' structures or traits have a common origin but can have dissimilar functions. Bird, bat, and pterosaur wings are analogous structures, but their forelimbs are homologous, sharing an ancestral state despite serving different functions. The opposite of convergence is divergent evolution, where related species evolve different traits. Convergent evolution is similar to parallel evo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Smith (botanist)
John Smith (1798–1888) was a British botanist who was the first curator at Royal Botanic Gardens, Kew (Kew Gardens), starting in 1841. He had first been employed at the gardens as a stove boy (stoking stoves to warm the greenhouses) in 1822. Along with the directors, Sir William Jackson Hooker and Sir Joseph Hooker, he oversaw the conversion of the gardens from private royal gardens to public gardens when Queen Victoria converted them, possibly saving them from oblivion. He further prevented the gardens from catastrophic decline during the late 19th century when they were neglected in funding priorities. According to the Kew website, "It is significant that when stove-boy-Smith arrived at Kew, 40 species of fern were grown but when Curator Smith retired, there were 1,084." He was born in Pittenweem, Scotland, in 1798. He died 12 February 1888 at Park House, Kew Road The A307 road runs through SW London and NW Surrey. It is primary at the north-east end; the remainder is ... [...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] |
Cheilanthes
''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 the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetraploid
Polyploidy is a condition in which the cells of an organism have more than one pair of ( homologous) chromosomes. Most species whose cells have nuclei (eukaryotes) are diploid, meaning they have two sets of chromosomes, where each set contains one or more chromosomes and comes from each of two parents, resulting in pairs of homologous chromosomes between sets. However, some organisms are polyploid. Polyploidy is especially common in plants. Most eukaryotes have diploid somatic cells, but produce haploid gametes (eggs and sperm) by meiosis. A monoploid has only one set of chromosomes, and the term is usually only applied to cells or organisms that are normally diploid. Males of bees and other Hymenoptera, for example, are monoploid. Unlike animals, plants and multicellular algae have life cycles with two alternating multicellular generations. The gametophyte generation is haploid, and produces gametes by mitosis, the sporophyte generation is diploid and produces spores by meio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myriopteris Scabra
''Myriopteris scabra'', previously known as ''Pellaea scabra'', ''Cheilanthes aspera'' or ''Cheilanthes horridula'', is a species of cheilanthoid fern with the common name rough lipfern. It is native to Mexico and to Texas in the United States. Description ''Myriopteris scabra'' grows from a short creeping rhizome, usually 4–7 mm in diameter with brown scales. The leaves (fronds) are clustered and may range greatly in size from 5–30 cm long. The leaf petiole is black to dark brown. The leaf blade is 1–4 cm wide, linear-oblong to lanceolate, and up to pinnate-pinnatifid to 2-pinnate. The rachis has scattered linear-lanceolate scales and dimorphic pubescence, abaxially sparsely hirsute, adaxially covered with tortuous appressed hairs. The ultimate leaflets are narrowly elliptic to elongate-deltate, not beadlike, and up to 3–5 mm long. The upper leaflet surface has a distinctive rough or spiky surface, which distinguishes this species from most other ''M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myriopteris Microphylla
''Myriopteris'', commonly known as the lip ferns, is a genus of cheilanthoid ferns. Like other cheilanthoids, they are ferns of dry habitats, reproducing both sexually and apogamously. Many species have leaves divided into a large number of small, bead-like segments, the probable inspiration for the generic name. Hairs and/or scales are often present on both the upper and lower surfaces of the leaf, and their presence and appearance are useful in distinguishing between species. The genus is most diverse in Mexico, but species are found from southwestern Canada south to southern Chile, and one species is endemic to southern Africa. Description No single morphological character divides ''Myriopteris'', as presently circumscribed, from the other cheilanthoids. Convergent evolution in arid environments is thought to be responsible for widespread homoplasy in the morphological characters traditionally used to classify this group. While small, bead-like ultimate segments are associate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myriopteris Lendigera
''Myriopteris lendigera'' is a species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ... of cheilanthoid fern with the common name nit-bearing lip fern. Description ''Myriopteris lendigera'' grows from long creeping rhizomes 1–3 mm in diameter with dark brown scales. Leaves can be scattered or clustered and range in length from 5 to 30 cm. The petiole is usually dark brown. The leaf blade is ovate-deltate to oblong-lanceolate and usually 4-pinnate (subdivided 3 times) at the leaf base. The blade is wide. The ultimate leaflet segments are round to slightly oblong and appear beadlike, with a diameter of 1–3 mm. Their abaxial (lower) surface is sparsely to moderately pubescent with coarse hairs and the adaxial (upper) surface is glabrous. Each leaflet curls under ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triploid
Polyploidy is a condition in which the cells of an organism have more than one pair of ( homologous) chromosomes. Most species whose cells have nuclei ( eukaryotes) are diploid, meaning they have two sets of chromosomes, where each set contains one or more chromosomes and comes from each of two parents, resulting in pairs of homologous chromosomes between sets. However, some organisms are polyploid. Polyploidy is especially common in plants. Most eukaryotes have diploid somatic cells, but produce haploid gametes (eggs and sperm) by meiosis. A monoploid has only one set of chromosomes, and the term is usually only applied to cells or organisms that are normally diploid. Males of bees and other Hymenoptera, for example, are monoploid. Unlike animals, plants and multicellular algae have life cycles with two alternating multicellular generations. The gametophyte generation is haploid, and produces gametes by mitosis, the sporophyte generation is diploid and produces spores by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
