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Winfrenatia
''Winfrenatia'' is a genus that contains the oldest-known terrestrial lichen, occurring in fossils preserved in the lower Devonian Rhynie chert. The genus contains the single species ''Winfrenatia reticulata'', named for the texture of its surface. Both the species and the genus were described in 1997. It comprises a thallus, made of layered, aseptate hyphae, with a number of depressions on its top surface. Each depression contains a net of hyphae holding a sheathed cyanobacterium. The fungus appears to be related to the Zygomycetes, and the photosynthetic partner of photobiont resembles the coccoid cyanobacteria ''Gloeocapsa ''Gloeocapsa'' (from the Greek ''gloia'' (gelatinous) and the Latin ''capsa'' (case)) is a genus of cyanobacteria. The cells secrete individual gelatinous sheaths which can often be seen as sheaths around recently divided cells within outer shea ...'' and '' Chroococcidiopsis''. There may be two separate algae, making the lichen a symbiosis of thre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lichen
A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.Introduction to Lichens – An Alliance between Kingdoms . University of California Museum of Paleontology. Lichens have properties different from those of their component organisms. They come in many colors, sizes, and forms and are sometimes plant-like, but are not s. They may have tiny, leafless branches (); flat leaf-like structures ( |
Lichen
A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.Introduction to Lichens – An Alliance between Kingdoms . University of California Museum of Paleontology. Lichens have properties different from those of their component organisms. They come in many colors, sizes, and forms and are sometimes plant-like, but are not s. They may have tiny, leafless branches (); flat leaf-like structures ( |
Rhynie Chert
The Rhynie chert is a Lower Devonian sedimentary deposit exhibiting extraordinary fossil detail or completeness (a Lagerstätte). It is exposed near the village of Rhynie, Aberdeenshire, Scotland; a second unit, the Windyfield chert, is located some 700 m away. The Rhynie chert contains exceptionally preserved plant, fungus, lichen and animal material preserved in place by an overlying volcanic deposit. The bulk of the Devonian fossil bed consists of primitive plants (which had water-conducting cells and sporangia, but no true leaves), along with arthropods, lichens, algae and fungi. This fossil bed is remarkable for two reasons. First, the age of the site ( Pragian, Early Devonian, formed about ) places it at an early stage in the colonisation of land. Second, these cherts are famous for their exceptional state of ultrastructural preservation, with individual cell walls easily visible in polished specimens. Stomata have been counted and lignin remnants detected in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus comes above species and below family (taxonomy), family. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus. :E.g. ''Panthera leo'' (lion) and ''Panthera onca'' (jaguar) are two species within the genus ''Panthera''. ''Panthera'' is a genus within the family Felidae. The composition of a genus is determined by taxonomy (biology), taxonomists. The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: # monophyly – all descendants ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fungi
A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from the other eukaryotic kingdoms, which by one traditional classification include Plantae, Animalia, Protozoa, and Chromista. A characteristic that places fungi in a different kingdom from plants, bacteria, and some protists is chitin in their cell walls. Fungi, like animals, are heterotrophs; they acquire their food by absorbing dissolved molecules, typically by secreting digestive enzymes into their environment. Fungi do not photosynthesize. Growth is their means of mobility, except for spores (a few of which are flagellated), which may travel through the air or water. Fungi are the principal decomposers in ecological systems. These and other differences place fungi in a single group of related organisms, named the ''Eumycota'' (''t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossil Taxa Described In 1997
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Paleontology is the study of fossils: their age, method of formation, and evolutionary significance. Specimens are usually considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years old to 4.1 billion years old. Early edition, published online before print. The observation in the 19th century that certain fossils were associated with certain rock strata led to the recognition of a geological timescale and the relative ages of different fossils. The development of radiometric dating techniques in the early 20th century allowed scientists to quantitatively measure the abso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Symbiosis
Symbiosis (from Greek , , "living together", from , , "together", and , bíōsis, "living") is any type of a close and long-term biological interaction between two different biological organisms, be it mutualistic, commensalistic, or parasitic. The organisms, each termed a symbiont, must be of different species. In 1879, Heinrich Anton de Bary defined it as "the living together of unlike organisms". The term was subject to a century-long debate about whether it should specifically denote mutualism, as in lichens. Biologists have now abandoned that restriction. Symbiosis can be obligatory, which means that one or more of the symbionts depend on each other for survival, or facultative (optional), when they can generally live independently. Symbiosis is also classified by physical attachment. When symbionts form a single body it is called conjunctive symbiosis, while all other arrangements are called disjunctive symbiosis."symbiosis." Dorland's Illustrated Medical Dictionary. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chroococcidiopsis
''Chroococcidiopsis'' is a photosynthetic, coccoidal bacterium. A diversity of species and cultures exist within the genus, with a diversity of phenotypes. Some extremophile members of the order Chroococidiopsidales are known for their ability to survive harsh environmental conditions, including both high and low temperatures, ionizing radiation, and high salinity. Desiccation resistance The ability of ''Chroococcidiopsis'' to resist desiccation in arid environments is due in part because it colonizes the underside of translucent rocks. The underside of these rocks provides enough condensed moisture for growth while the rock's translucent nature allows just enough light to reach the organism for photosynthesis to occur. Mars colonization Due to its resistance to harsh environmental conditions, especially low temperature, low moisture, and radiation tolerance, ''Chroococcidiopsis'' has been thought of as an organism capable of living on Mars. Scientists have speculated about the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gloeocapsa
''Gloeocapsa'' (from the Greek ''gloia'' (gelatinous) and the Latin ''capsa'' (case)) is a genus of cyanobacteria. The cells secrete individual gelatinous sheaths which can often be seen as sheaths around recently divided cells within outer sheaths. Recently divided cell pairs often appear to be only one cell since the new cells cohere temporarily. They are also known as glow caps, a term derived from the yellowish hue given off by the cap. Occurrence Some species of this genus are halophiles and hence found in hypersaline lakes and other high salinity environments. An example of such occurrence of the genus is in the Makgadikgadi Pans of Botswana Botswana (, ), officially the Republic of Botswana ( tn, Lefatshe la Botswana, label= Setswana, ), is a landlocked country in Southern Africa. Botswana is topographically flat, with approximately 70 percent of its territory being the Kalaha .... '' Gloeocapsa magma'' is noted for colonising roof shingles in the United States an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coccus
A coccus (plural cocci) is any bacterium or archaeon that has a spherical, ovoid, or generally round shape. Bacteria are categorized based on their shapes into three classes: cocci (spherical-shaped), bacillus (rod-shaped) and spiral ( of which there are two types: spirillum and spirochete). Coccus refers to the shape of the bacteria, and can contain multiple genera, such as staphylococci or streptococci. Cocci can grow in pairs, chains, or clusters, depending on their orientation and attachment during cell division. In contrast to many bacilli-shaped bacteria, most cocci bacteria do not have flagella and are non-motile. Cocci is an English loanword of a modern or neo-Latin noun, which in turn stems from the Greek masculine noun () meaning 'berry'. Structure The cell wall structure for cocci may vary between gram-positive (thick peptidoglycan layers) and gram-negative (thin peptidoglycan layers). While living in their host organism, cocci can be pathogenic (e.g., streptoco ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zygomycota
Zygomycota, or zygote fungi, is a former division or phylum of the kingdom Fungi. The members are now part of two phyla: the Mucoromycota and Zoopagomycota. Approximately 1060 species are known. They are mostly terrestrial in habitat, living in soil or on decaying plant or animal material. Some are parasites of plants, insects, and small animals, while others form symbiotic relationships with plants. Zygomycete hyphae may be coenocytic, forming septa only where gametes are formed or to wall off dead hyphae. Zygomycota is no longer recognised as it was not believed to be truly monophyletic. Etymology The name ''Zygomycota'' refers to the zygosporangia characteristically formed by the members of this clade, in which resistant spherical spores are formed during sexual reproduction. ''Zygos'' is Greek for "joining" or "a yoke", referring to the fusion of two hyphal strands which produces these spores, and ''-mycota'' is a suffix referring to a division of fungi. Spores The ter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyanobacterium
Cyanobacteria (), also known as Cyanophyta, are a phylum of gram-negative bacteria that obtain energy via photosynthesis. The name ''cyanobacteria'' refers to their color (), which similarly forms the basis of cyanobacteria's common name, blue-green algae, although they are not usually scientifically classified as algae. They appear to have originated in a freshwater or terrestrial environment. Sericytochromatia, the proposed name of the paraphyletic and most basal group, is the ancestor of both the non-photosynthetic group Melainabacteria and the photosynthetic cyanobacteria, also called Oxyphotobacteria. Cyanobacteria use photosynthetic pigments, such as carotenoids, phycobilins, and various forms of chlorophyll, which absorb energy from light. Unlike heterotrophic prokaryotes, cyanobacteria have internal membranes. These are flattened sacs called thylakoids where photosynthesis is performed. Phototrophic eukaryotes such as green plants perform photosynthesis in plastids t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
