|
Stirtonia Curvata
''Stirtonia curvata'' is a species of crustose lichen belonging to the family Arthoniaceae. It was formally described as a new species in 2009 based on specimens collected from Indonesia. Taxonomy ''Stirtonia curvata'' was described by the Dutch lichenologist André Aptroot from specimens collected by Willem Vink in 1959 near Manokwari in Irian Jaya, Indonesia. The species epithet ''curvata'' refers to the often curved shape of its . The genus '' Stirtonia'' includes lichens with distinctive areas that lack a true hymenium, have round asci, and thick-walled, septate ascospores. Description ''Stirtonia curvata'' has a crustose, smooth thallus that spreads over an area up to about 5 cm in diameter. It is typically whitish-yellow to brownish, thin (less than 0.1 mm), and somewhat shiny in appearance. The thallus contains calcium oxalate crystals, detectable under the microscope. The areas, where the reproductive structures are located, appear as angular or linear zo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
André Aptroot
André Aptroot ( Heemskerk, 1961) is a Dutch mycologist and lichenologist. His primary research focus is on biodiversity, particularly tropical lichens, encompassing systematics, floristic surveys, and taxonomic reviews. A prolific researcher, he has published more than 500 scientific papers and described hundreds of new fungal and lichen species. Career In 1993 he did his PhD at the University of Utrecht under the supervision of Robbert Gradstein (nl). His dissertation was titled "Systematic studies on pyrenocarpous lichens and related fungi". He specializes in fungi and lichens on which he has several hundreds of publications to his name. He has worked as curator at Centraalbureau voor Schimmelcultures (now Westerdijk Institute). Aptroot is the founder of the ''Adviesbureau voor Bryologie en Lichenologie – Herbarium'' (Consultancy for Bryology and Lichenology), which is located in Soest where there is a herbarium with a collection of lichens mainly from the Ne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcium Oxalate
Calcium oxalate (in archaic terminology, oxalate of lime) is a calcium salt of oxalic acid with the chemical formula or . It forms hydrates , where ''n'' varies from 1 to 3. Anhydrous and all hydrated forms are colorless or white. The monohydrate occurs naturally as the mineral whewellite, forming envelope-shaped crystals, known in plants as raphides. The two rarer hydrates are dihydrate , which occurs naturally as the mineral weddellite, and trihydrate , which occurs naturally as the mineral caoxite, are also recognized. Some foods have high quantities of calcium oxalates and can produce sores and numbing on ingestion and may even be fatal. Cultural groups with diets that depend highly on fruits and vegetables high in calcium oxalate, such as those in Micronesia, reduce the level of it by boiling and cooking them. They are a constituent in 76% of human kidney stones. Calcium oxalate is also found in beerstone, a scale that forms on containers used in breweries. Occurrence ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lichens Described In 2009
A lichen ( , ) is a hybrid colony of algae or cyanobacteria living symbiotically among filaments of multiple fungus species, along with yeasts and bacteria embedded in the cortex or "skin", in a mutualistic relationship.Introduction to Lichens – An Alliance between Kingdoms . University of California Museum of Paleontology. . Lichens are the lifeform that first brought the term symbiosis (as ''Symbiotismus'') into biological context. Lichens have since been recognized as important actors in and producers which many higher trophic feeders feed on, such as reindeer, gastropods, nematodes, mites, and springtails. Lich ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lichen Species
A lichen ( , ) is a hybrid colony (biology), colony of algae or cyanobacteria living symbiotically among hypha, filaments of multiple fungus species, along with yeasts and bacteria embedded in the cortex or "skin", in a mutualism (biology), mutualistic relationship.Introduction to Lichens – An Alliance between Kingdoms . University of California Museum of Paleontology. . Lichens are the lifeform that first brought the term symbiosis (as ''Symbiotismus'') into biological context. Lichens have since been recognized as important actors in nutrient cycling and producers which many higher trophic feeders feed on, such as reindeer, gastropods, nematodes, mites, and springtails. Lichens have properties different from those of their component organisms. They come in man ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Java
Java is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea (a part of Pacific Ocean) to the north. With a population of 156.9 million people (including Madura) in mid 2024, projected to rise to 158 million at mid 2025, Java is the world's List of islands by population, most populous island, home to approximately 55.7% of the Demographics of Indonesia, Indonesian population (only approximately 44.3% of Indonesian population live outside Java). Indonesia's capital city, Jakarta, is on Java's northwestern coast. Many of the best known events in Indonesian history took place on Java. It was the centre of powerful Hindu-Buddhist empires, the Islamic sultanates, and the core of the colonial Dutch East Indies. Java was also the center of the History of Indonesia, Indonesian struggle for independence during the 1930s and 1940s. Java dominates Indonesia politically, economically and culturally. Four of Indonesia's eig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Western New Guinea
Western New Guinea, also known as Papua, Indonesian New Guinea, and Indonesian Papua, is the western half of the island of New Guinea, formerly Dutch and granted to Indonesia in 1962. Given the island is alternatively named Papua, the region is also called West Papua (). It is one of the seven geographical units of Indonesia in ISO 3166-2:ID. Lying to the west of Papua New Guinea and geographically a part of the Australian continent, the territory is almost entirely in the Southern Hemisphere and includes the Biak and Raja Ampat archipelagoes. The region is predominantly covered with rainforest where traditional peoples live, including the Dani of the Baliem Valley. A large proportion of the population live in or near coastal areas. The largest city is Jayapura. The island of New Guinea has been populated for tens of thousands of years. European traders began frequenting the region around the late 16th century due to spice trade. In the end, the Dutch Empire emerged ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lowland
Upland and lowland are conditional descriptions of a plain based on elevation above sea level. In studies of the ecology of freshwater rivers, habitats are classified as upland or lowland. Definitions Upland and lowland are portions of a plain that are conditionally categorized by their elevation above the sea level. Lowlands are usually no higher than , while uplands are somewhere around to . On unusual occasions, certain lowlands such as the Caspian Depression lie below sea level. Uplands areas tend to spike into valleys and mountains, forming mountain ranges while lowland areas tend to be uniformly flat, although both can vary such as the Mongolian Plateau. Upland habitats are cold, clear and rocky whose rivers are fast-flowing in mountainous areas; lowland habitats are warm with slow-flowing rivers found in relatively flat lowland areas, with water that is frequently colored by sediment and organic matter. These classifications overlap with the geological definitions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spot Test (lichen)
A spot test in lichenology is a spot analysis used to help identify lichens. It is performed by placing a drop of a chemical reagent on different parts of the lichen and noting the colour change (or lack thereof) associated with application of the chemical. The tests are routinely encountered in dichotomous keys for lichen species, and they take advantage of the wide array of lichen products (secondary metabolites) produced by lichens and their uniqueness among taxa. As such, spot tests reveal the presence or absence of chemicals in various parts of a lichen. They were first proposed as a method to help identify species by the Finnish lichenologist William Nylander in 1866. Three common spot tests use either 10% aqueous KOH solution (K test), saturated aqueous solution of bleaching powder or calcium hypochlorite (C test), or 5% alcoholic ''p''-phenylenediamine solution (P test). The colour changes occur due to presence of particular secondary metabolites in the lichen. In ide ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iodine
Iodine is a chemical element; it has symbol I and atomic number 53. The heaviest of the stable halogens, it exists at standard conditions as a semi-lustrous, non-metallic solid that melts to form a deep violet liquid at , and boils to a violet gas at . The element was discovered by the French chemist Bernard Courtois in 1811 and was named two years later by Joseph Louis Gay-Lussac, after the Ancient Greek , meaning 'violet'. Iodine occurs in many oxidation states, including iodide (I−), iodate (), and the various periodate anions. As the heaviest essential mineral nutrient, iodine is required for the synthesis of thyroid hormones. Iodine deficiency affects about two billion people and is the leading preventable cause of intellectual disabilities. The dominant producers of iodine today are Chile and Japan. Due to its high atomic number and ease of attachment to organic compounds, it has also found favour as a non-toxic radiocontrast material. Because of the spec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ellipsoid
An ellipsoid is a surface that can be obtained from a sphere by deforming it by means of directional Scaling (geometry), scalings, or more generally, of an affine transformation. An ellipsoid is a quadric surface; that is, a Surface (mathematics), surface that may be defined as the zero set of a polynomial of degree two in three variables. Among quadric surfaces, an ellipsoid is characterized by either of the two following properties. Every planar Cross section (geometry), cross section is either an ellipse, or is empty, or is reduced to a single point (this explains the name, meaning "ellipse-like"). It is Bounded set, bounded, which means that it may be enclosed in a sufficiently large sphere. An ellipsoid has three pairwise perpendicular Rotational symmetry, axes of symmetry which intersect at a Central symmetry, center of symmetry, called the center of the ellipsoid. The line segments that are delimited on the axes of symmetry by the ellipsoid are called the ''principal ax ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thallus
Thallus (: thalli), from Latinized Greek (), meaning "a green shoot" or "twig", is the vegetative tissue of some organisms in diverse groups such as algae, fungi, some liverworts, lichens, and the Myxogastria. A thallus usually names the entire body of a multicellular non-moving organism in which there is no organization of the tissues into organs. Many of these organisms were previously known as the thallophytes, a polyphyletic group of distantly related organisms. An organism or structure resembling a thallus is called thalloid, thalloidal, thalliform, thalline, or thallose. Even though thalli do not have organized and distinct parts ( leaves, roots, and stems) as do the vascular plants, they may have analogous structures that resemble their vascular "equivalents". The analogous structures have similar function or macroscopic structure, but different microscopic structure; for example, no thallus has vascular tissue. In exceptional cases such as the Lemnoideae, where th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
