Valdiviathyris

	Valdiviathyris ''Valdiviathyris'' is a genus of craniate brachiopods that has changed little since the Silurian, from when fossils are known. The extant species ''V. quenstedti'' is known from the late Eocene. It was initially known only from the holotype collected from the southern Indian Ocean, near Île Saint-Paul, at a depth of . The specimen is considered to be adolescent and has a thin (0.1 mm thick) calcareous dorsal valve. This has an irregular conical shape, with the tip (or apex) not coinciding with the middle, and is on the outside only adorned by growth lines. On the inside it has pits (or punctae) that branch into four or five canals further to the outside. More recent specimens have been found near New Zealand. As long as no fossils of ''Vadiviathyris'' are found dating between the Silurian and the Eocene, this genus can be regarded a Lazarus taxon In paleontology, a Lazarus taxon (plural ''taxa'') is a taxon that disappears for one or more periods from the fossil record ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Valdiviathyris Quenstedti ''Valdiviathyris quenstedti'' is a small species of brachiopods with a maximum size of about wide. Distribution Occurrence over time Specimens attributed to ''V. quenstedti'' from the Upper Eocene have been found near New Zealand. Recent distribution ''V. quenstedti'' has been found near Chile and around New Zealand, but is assumed to be widespread in the Southern Ocean on hard (rock) substrates. Ecology ''V. quenstedti'' is found in cryptic environments together with species of ''Novocrania''. Description The largest specimen found is 6mm length, 7mm wide and 2½mm height. Both valves are very thin and translucent, have small pores (a state called punctate by science) and are obliquely conical in profile with the tip close to the straight posterior margin. The exteriors of the valves have irregular hummocks, and hollows with occasional pustules and some concentric growth lines. The valves vary in shape from subquadrate to subhexagonal, fitting the rock crevice in w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several examples, but explicitly designated as the holotype. Under the International Code of Zoological Nomenclature (ICZN), a holotype is one of several kinds of name-bearing types. In the International Code of Nomenclature for algae, fungi, and plants (ICN) and ICZN, the definitions of types are similar in intent but not identical in terminology or underlying concept. For example, the holotype for the butterfly '' Plebejus idas longinus'' is a preserved specimen of that subspecies, held by the Museum of Comparative Zoology at Harvard University. In botany, an isotype is a duplicate of the holotype, where holotype and isotypes are often pieces from the same individual plant or samples from the same gathering. A holotype is not necessarily "typ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Brachiopod Genera Brachiopods (), phylum Brachiopoda, are a phylum of trochozoan animals that have hard "valves" (shells) on the upper and lower surfaces, unlike the left and right arrangement in bivalve molluscs. Brachiopod valves are hinged at the rear end, while the front can be opened for feeding or closed for protection. Two major categories are traditionally recognized, articulate and inarticulate brachiopods. The word "articulate" is used to describe the tooth-and-groove structures of the valve-hinge which is present in the articulate group, and absent from the inarticulate group. This is the leading diagnostic skeletal feature, by which the two main groups can be readily distinguished as fossils. Articulate brachiopods have toothed hinges and simple, vertically-oriented opening and closing muscles. Conversely, inarticulate brachiopods have weak, untoothed hinges and a more complex system of vertical and oblique (diagonal) muscles used to keep the two valves aligned. In many brachiopods, a s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Craniata A craniate is a member of the Craniata (sometimes called the Craniota), a proposed clade of chordate animals with a skull of hard bone or cartilage. Living representatives are the Myxini (hagfishes), Hyperoartia (including lampreys), and the much more numerous Gnathostomata (jawed vertebrates).Campbell & Reece 2005 p. 676 Formerly distinct from vertebrates by including hagfish, molecular and anatomical research in the 21st century has led to the reinclusion of hagfish as vertebrates, making living craniates synonymous with living vertebrates. The clade was conceived largely on the basis of the Hyperoartia (lampreys and kin) being more closely related to the Gnathostomata (jawed vertebrates) than the Myxini (hagfishes). This, combined with an apparent lack of vertebral elements within the Myxini, suggested that the Myxini were descended from a more ancient lineage than the vertebrates, and that the skull developed before the vertebral column. The clade was thus composed of the Myx ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Lazarus Taxon In paleontology, a Lazarus taxon (plural ''taxa'') is a taxon that disappears for one or more periods from the fossil record, only to appear again later. Likewise in conservation biology and ecology, it can refer to species or populations that were thought to be extinct, and are rediscovered. The term Lazarus taxon was coined by Karl W. Flessa & David Jablonski in 1983 and was then expanded by Jablonski in 1986. Paul Wignall and Michael Benton defined Lazarus taxa as, "At times of biotic crisis many taxa go extinct, but others only temporarily disappeared from the fossil record, often for intervals measured in millions of years, before reappearing unchanged". Earlier work also supports the concept though without using the name Lazarus taxon, like work by Christopher R. C. Paul. The term refers to the story in the Christian biblical Gospel of John, in which Jesus Christ raised Lazarus from the dead. Potential explanations Lazarus taxa are observational artifacts that app ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Anatomical Terms Of Location Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position provides a definition of what is at the front ("anterior"), behind ("posterior") and so on. As part of defining and describing terms, the body is described through the use of anatomical planes and anatomical axes. The meaning of terms that are used can change depending on whether an organism is bipedal or quadrupedal. Additionally, for some animals such as invertebrates, some terms may not have any meaning at all; for example, an animal that is radially symmetrical will have no anterior surface, but can still have a description that a part is close to the middle ("proximal") or further from the middle ("distal"). International organisations have determined vocabularies that are often used as standard vocabularies for subdisciplines of anatom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Île Saint-Paul Île Saint-Paul (Saint Paul Island) is an island forming part of the French Southern and Antarctic Lands (''Terres australes et antarctiques françaises'', TAAF) in the Indian Ocean, with an area of . The island is located about south of the larger Île Amsterdam (), northeast of the Kerguelen Islands, and southeast of Réunion. It is an important breeding site for seabirds. A scientific research cabin on the island is used for scientific or ecological short campaigns, but there is no permanent population. It is under the authority of a senior administrator on Réunion. Geography Île Saint-Paul is a volcanic island with triangular in shape that measures no more than at its widest point. It is the top of an active volcano; the volcano last erupted in 1793 (from its SW Flank), and is rocky with steep cliffs on the east side. The thin stretch of rock that used to close off the crater collapsed in 1780, admitting the sea through a channel; the entrance is only a few meters d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Indian Ocean The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or ~19.8% of the water on Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia to the east. To the south it is bounded by the Southern Ocean or Antarctica, depending on the definition in use. Along its core, the Indian Ocean has some large marginal or regional seas such as the Arabian Sea, Laccadive Sea, Bay of Bengal, and Andaman Sea. Etymology The Indian Ocean has been known by its present name since at least 1515 when the Latin form ''Oceanus Orientalis Indicus'' ("Indian Eastern Ocean") is attested, named after Indian subcontinent, India, which projects into it. It was earlier known as the ''Eastern Ocean'', a term that was still in use during the mid-18th century (see map), as opposed to the ''Western Ocean'' (Atlantic Ocean, Atlantic) before the Pacific Ocean, Pacific was surmised. Conversely, Ming treasure voyages, Chinese explorers in the Indian Oce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Portable Document Format Portable Document Format (PDF), standardized as ISO 32000, is a file format developed by Adobe in 1992 to present documents, including text formatting and images, in a manner independent of application software, hardware, and operating systems.Adobe Systems IncorporatedPDF Reference, Sixth edition, version 1.23 (53 MB) Nov 2006, p. 33. Archiv/ref> Based on the PostScript language, each PDF file encapsulates a complete description of a fixed-layout flat document, including the text, fonts, vector graphics, raster images and other information needed to display it. PDF has its roots in "The Camelot Project" initiated by Adobe co-founder John Warnock in 1991. PDF was standardized as ISO 32000 in 2008. The last edition as ISO 32000-2:2020 was published in December 2020. PDF files may contain a variety of content besides flat text and graphics including logical structuring elements, interactive elements such as annotations and form-fields, layers, rich media (including video con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Eocene The Eocene ( ) Epoch is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', "dawn") and (''kainós'', "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch. The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope Carbon-13, 13C in the atmosphere was exceptionally low in comparison with the more common isotope Carbon-12, 12C. The end is set at a major extinction event called the ''Grande Coupure'' (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Popigai impact structure, Siberia and in what is now ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Palaeontology (journal) ''Palaeontology'' is one of the two scientific journals of the Palaeontological Association (the other being '' Papers in Palaeontology''). It was established in 1957 and is published on behalf of the Association by Wiley-Blackwell. The editor-in-chief is Barry Lomax (University of Nottingham). ''Palaeontology'' publishes articles on a range of palaeontological topics, including taphonomy, functional morphology, systematics, palaeo-environmental reconstruction and biostratigraphy. According to the ''Journal Citation Reports'', the journal has a 2017 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a scientometric index calculated by Clarivate that reflects the yearly mean number of citations of articles published in the last two years in a given journal, as i ... of 3.730, ranking it 1st out of 55 journals in the category "Paleontology". References External links * Paleontology journals Publications established in 1957 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Systematics And Biodiversity ''Systematics and Biodiversity'' is a peer-reviewed scientific journal covering all aspects of whole-organism biology. It is published by Taylor & Francis on behalf of The Natural History Museum. Abstracting and indexing The journal is abstracted or indexed in: * Science Citation Index Expanded Scopus EBSCO databases * ProQuest databases According to the ''Journal Citation Reports'', the journal has a 2021 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a scientometric index calculated by Clarivate that reflects the yearly mean number of citations of articles published in the last two years in a given journal, as i ... of 2.313. References External links {{Official website, 1=https://www.tandfonline.com/action/journalInformation?journalCode=tsab20 English-language journals Publications with year of establishment missing Taylor & Francis academic journals Systematics journals ... [...More Info...] [...Related Items...] OR:* [Wikipedia] [Google] [Baidu]