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Spikemoss
''Selaginella'' is the sole genus of vascular plants in the family Selaginellaceae, the spikemosses or lesser clubmosses. This family is distinguished from Lycopodiaceae (the clubmosses) by having scale-leaves bearing a ligule and by having spores of two types. They are sometimes included in an informal paraphyletic group called the " fern allies". '' S. moellendorffii'' is an important model organism. Its genome has been sequenced by the United States Department of Energy's Joint Genome Institute. The name ''Selaginella'' was erected by Palisot de Beauvois solely for the species '' Selaginella selaginoides'', which turns out (with the closely related '' Selaginella deflexa'') to be a clade that is sister to all other ''Selaginellas'', so any definitive subdivision of the species into separate genera leaves two taxa in ''Selaginella'', with the hundreds of other species in new or resurrected genera. ''Selaginella'' occurs mostly in the tropical regions of the world, with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Selaginella Deflexa
''Selaginella'' is the sole genus of vascular plants in the family Selaginellaceae, the spikemosses or lesser clubmosses. This family is distinguished from Lycopodiaceae (the clubmosses) by having scale-leaves bearing a ligule and by having spores of two types. They are sometimes included in an informal paraphyletic group called the " fern allies". '' S. moellendorffii'' is an important model organism. Its genome has been sequenced by the United States Department of Energy's Joint Genome Institute. The name ''Selaginella'' was erected by Palisot de Beauvois solely for the species '' Selaginella selaginoides'', which turns out (with the closely related '' Selaginella deflexa'') to be a clade that is sister to all other ''Selaginellas'', so any definitive subdivision of the species into separate genera leaves two taxa in ''Selaginella'', with the hundreds of other species in new or resurrected genera. ''Selaginella'' occurs mostly in the tropical regions of the world, with a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Selaginella Selaginoides
''Selaginella selaginoides'' is a non-flowering plant of the spikemoss genus ''Selaginella'' with a wide distribution around the Northern Hemisphere. It resembles a moss in appearance but is a vascular plant belonging to the division Lycopodiophyta. It has a number of common names including lesser clubmoss, club spikemoss, northern spikemoss, low spikemoss and prickly mountain-moss. This plant has one close relative, ''Selaginella deflexa'', native to Hawaii. These two plants form a small clade that is sister to all other ''Selaginella'' species. Description It is a small, delicate, low-growing plant. Its perennial sterile stems are short, slender and irregularly branched reaching up to 15 cm in length. They creep along the ground but usually turn upwards near the tip. They have small, pointed, triangular leaves about 1–2 mm long, each bearing a ligule on its upper surface near the base. The plant also produces annual fertile shoots. They are more robust th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lycopodiopsida
Lycopodiopsida is a class of vascular plants known as lycopods, lycophytes or other terms including the component lyco-. Members of the class are also called clubmosses, firmosses, spikemosses and quillworts. They have dichotomously branching stems bearing simple leaves called microphylls and reproduce by means of spores borne in sporangia on the sides of the stems at the bases of the leaves. Although living species are small, during the Carboniferous, extinct tree-like forms formed huge forests that dominated the landscape and contributed to coal deposits. The nomenclature and classification of plants with microphylls varies substantially among authors. A consensus classification for extant (living) species was produced in 2016 by the Pteridophyte Phylogeny Group (PPG I), which places them all in the class Lycopodiopsida, which includes the classes Isoetopsida and Selaginellopsida used in other systems. (See Table 2.) Alternative classification systems have used ranks f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fern Ally
Fern allies are a diverse group of seedless vascular plants that are not true ferns. Like ferns, a fern ally disperses by shedding spores to initiate an alternation of generations. Classification Originally, three or four groups of plants were considered to be fern allies. In various classification schemes, these may be grouped as classes or divisions within the plant kingdom. Fern allies and ferns were sometimes grouped together as division Pteridophyta. Another traditional classification scheme of living plants is as follows (here, the first three classes are the "fern allies"): *Kingdom: Plantae **Division Tracheophyta (vascular plants) ***Class Lycopsida, clubmosses and related plants (fern-allies) ***Class Sphenopsida or Equisetopsida, horsetails and scouring-rushes (fern-allies) ***Class Psilopsida, whisk ferns (fern-allies) ***Class Filices or Pteropsida, true ferns ***Class Spermatopsida (or sometimes as several different classes of seed-bearing plants) More re ... [...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] |
Antoine Frédéric Spring
Antoine Frédéric Spring (8 April 1814 in Gerolsbach, Bavaria – 17 January 1872) was a German-born, Belgian physician and botanist. He studied botany and medicine at the University of Munich, obtaining his PhD in 1835 and his medical doctorate during the following year. From 1839 to 1872 he was a professor at the University of Liège, initially in the fields of physiology and anatomy, later teaching classes in pathology and internal medicine. As a botanist he specialized in research of Lycopodiaceae (clubmosses) and Selaginellaceae (spikemosses), and was the binomial author of numerous species from both families. List of plants described and co-described b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Selaginella Kraussiana
''Selaginella kraussiana'' is a species of vascular plant in the family Selaginellaceae. It is referred to by the common names Krauss' spikemoss, Krauss's clubmoss, or African clubmoss, and is found naturally in parts of Sub-Saharan Africa and in Macaronesia. It belongs to the very ancient lineage of plants known as the clubmosses. Description Growing to just high, it is a low-growing, mat-forming evergreen perennial with primitive fern-like leaves, that spreads via rooting stems. Seginella kraussiana.jpg, Illustrating greener coloration when grown in brighter light Selaginella kraussiana OB10.1.jpg, Close-up of the foliage Distribution Its native distribution is the Macaronesia, and parts of south and east Africa. Its native distribution in the Azores was controversial up until 2005, when spores of this species were discovered in 6,000-year-old fossils on Pico. Since its introduction to Britain in 1878 it has spread slowly, and was first recorded in the wild in 1917 in wes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ligule
A ligule (from "strap", variant of ''lingula'', from ''lingua'' "tongue") is a thin outgrowth at the junction of leaf and leafstalk of many Poaceae, grasses (Poaceae) and Cyperaceae, sedges. A ligule is also a strap-shaped extension of the corolla (flower), corolla, such as that of a ray floret in plants in the daisy family Asteraceae. Poaceae and Cyperaceae The ligule is part of the leaf that is found at the junction of the blade and sheath of the leaf. It may take several forms, but it is commonly some form of translucent membrane or a fringe of hairs. The membranous ligule can be very short 1–2 mm (Kentucky bluegrass, ''Poa pratensis'') to very long 10–20 mm (Johnson grass, ''Sorghum halepense''), it can also be smooth on the edge or very ragged. Some grasses do not have a ligule, for example barnyardgrass (''Echinochloa crus-galli''). A ligule can also be defined as a membrane-like tissue or row of delicate hairs typically found in grasses at the juncti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Casparian Strips
The Casparian strip is a band-like thickening in the center of the root endodermis (radial and tangential walls of endodermal cells) of vascular plants (Pteridophytes and Spermatophytes). The composition of the region is mainly suberin, lignin and some structural proteins, which are capable of reducing the diffusive apoplastic flow of water and solutes into the stele and its width varies between species. The Casparian strip is impervious to water so can control the transportation of water and inorganic salts between the cortex and the vascular bundle, preventing water and inorganic salts from being transported to the stele through the apoplast, so that it must enter the cell membrane and move to the stele through the symplastic pathway, blocking the internal and external objects of the cell. The function and function of mass transportation are similar to that of animal tissues.. The development of the Casparian strip is regulated by transcription factors such as SHORT-ROOT (SH ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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