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Cambropycnogon
''Cambropycnogon'' is an extinct genus of pycnogonid arthropods. The genus contains a single species, ''Cambropycnogon klausmuelleri'', represented by presumed larval remains from the Upper Cambrian Orsten, having been referred to before description as "Larva D". Description ''Cambropycnogon'' is an early-stage pycnogonid larva (although this classification has been disputed) around 270 micrometers long, with three pairs of post-cheliceral appendages as well as the chelicerae that mark it as a possible pycnogonid. It also has two large caudal growths from its posterior end, the purpose of which is unknown. ''Cambropycnogon'' is covered in small spines roughly 1 micrometer long, as well as larger thorns behind its gnathobases. Its chelicerae are short and stout, resembling pincers, and the larva has a relatively large head shield. ''Cambropycnogon''s morphology matches that of early sea spider larvae such as the protonymph and semaphoront, with it being markedly distinct from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pycnogonid Genera
Sea spiders are marine arthropods of the class Pycnogonida, hence they are also called pycnogonids (; named after ''Pycnogonum'', the type genus; with the suffix '). The class includes the only now-living order Pantopoda ( ‘all feet’), alongside a few fossil species which could trace back to the early or mid Paleozoic. They are cosmopolitan, found in oceans around the world. The over 1,300 known species have leg spans ranging from to over . Most are toward the smaller end of this range in relatively shallow depths; however, they can grow to be quite large in Antarctic and deep waters. Despite their name and brief resemblance, "sea spiders" are not spiders, nor even arachnids. While some literature around the 2000s suggests they may be a sister group to all other living arthropods, their traditional classification as a member of chelicerates alongside horseshoe crabs and arachnids has regained wide support in subsequent studies. Morphology Many sea spiders are recognised ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orsten
The Orsten fauna are fossilized organisms preserved in the Orsten lagerstätte of Cambrian (Late Miaolingian to Furongian) rocks, notably at Kinnekulle and on the island of Öland, all in Sweden. The initial site, discovered in 1975 by Klaus Müller and his assistants, exceptionally preserves soft-bodied organisms, and their larvae, who are preserved uncompacted in three dimensions. The fossils are phosphatized and silicified, thus the delicate chitinous cuticle and soft parts are not affected by acids, which act upon the limestone nodules within which the fossils have survived. Acids dissolve the limestone, revealing the microfossils in a recovery process called "acid etching". To recover the fossils, more than one and a half tons of Orsten limestone have been dissolved in acid, originally in a specifically designed laboratory in Bonn, more recently moved to Ulm. The insoluble residue is scanned by electron microscope. The phosphorus used to replace the fossils with calcium p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthropods
Arthropods ( ) are invertebrates in the phylum Arthropoda. They possess an arthropod exoskeleton, exoskeleton with a cuticle made of chitin, often Mineralization (biology), mineralised with calcium carbonate, a body with differentiated (Metamerism (biology), metameric) Segmentation (biology), segments, and paired jointed appendages. In order to keep growing, they must go through stages of moulting, a process by which they shed their exoskeleton to reveal a new one. They form an extremely diverse group of up to ten million species. Haemolymph is the analogue of blood for most arthropods. An arthropod has an open circulatory system, with a body cavity called a haemocoel through which haemolymph circulates to the interior Organ (anatomy), organs. Like their exteriors, the internal organs of arthropods are generally built of repeated segments. They have ladder-like nervous systems, with paired Anatomical terms of location#Dorsal and ventral, ventral Ventral nerve cord, nerve cord ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monotypic Taxon
In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of Genus, genera, the term "unispecific" or "monospecific" is sometimes preferred. In botanical nomenclature, a monotypic genus is a genus in the special case where a genus and a single species are simultaneously described. Theoretical implications Monotypic taxa present several important theoretical challenges in biological classification. One key issue is known as "Gregg's Paradox": if a single species is the only member of multiple hierarchical levels (for example, being the only species in its genus, which is the only genus in its family), then each level needs a distinct definition to maintain logical structure. Otherwise, the different taxonomic ranks become effectively identical, which creates problems for organizing biological diversity in a hierarchical o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Klaus J
Klaus is a German, Dutch and Scandinavian given name and surname. It originated as a short form of Nikolaus, a German form of the Greek given name Nicholas. Notable persons whose family name is Klaus * Billy Klaus (1928–2006), American baseball player * Chris Klaus (born 1973), American entrepreneur * Felix Klaus (born 1992), German football player, son of Fred Klaus * Frank Klaus (1887–1948), German-American boxer, 1913 Middleweight Champion * Fred Klaus (born 1967), German football player and manager, father of Felix Klaus *Josef Klaus (1910–2001), Chancellor of Austria 1966–1970 *Karl Ernst Claus (1796–1864), Russian chemist *Václav Klaus (born 1941), Czech politician, former President of the Czech Republic * Walter K. Klaus (1912–2012), American politician and farmer Notable persons whose given name is Klaus * Brother Klaus, Swiss patron saint * Klaus Augenthaler (born 1957), German football player and manager * Klaus Badelt (born 1967), German composer *Kl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kinnekulle
Kinnekulle is a flat-topped mountain in the county of Västergötland, southwestern Sweden, on the eastern shore of lake Vänern. Its highest point is above sea level. The mountain is long and wide at the top. Geology Despite its enormous size, Kinnekulle is actually the smaller remnant of a much larger plateau, long ago worn down to a flat plain. Some 550 million years ago, in the Neoproterozoic, Neoproterozoic Era, the bottom-most rock of the plateau was under the sea. Layers of sedimentary rock formed over that layer from sand, mud, and sea animal remains. About 200 million years ago, during the Mesozoic, Mesozoic era, the area was uplifted above the sea. Tectonics, Tectonic activity forced molten lava through the sedimentary rock, creating sheetlike layers of diabase. These layers, when present, protected the softer sedimentary rock beneath them from erosion, resulting in mesa-like mountains such as Kinnekulle and its neighbours. History The historic town and ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
