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Protocinctus
''Protocinctus'' is a genus of cinctan and, , it is the oldest such recognized genus. It is known from the Wuliuan age of the Mansilla Formation, Zaragoza Zaragoza (), traditionally known in English as Saragossa ( ), is the capital city of the province of Zaragoza and of the autonomous communities of Spain, autonomous community of Aragon, Spain. It lies by the Ebro river and its tributaries, the ..., Spain. It is represented by the single species ''Protocinctus mansillaensis''. Description The genus bears a combination of characters unique to cinctans, with an elongated oval-shaped theca with a single anterior left marginal feeding groove, and a posterior marginal frame open in posterior ventral view. Like other cinctans, they would have been active pharyngeal filter feeders. The animal would lay close to the sediment surface with the anterior region oriented downstream and generate an inhalant flow of water directing suspended food particles to the mouth. Referen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cincta
Cincta is an extinct class of echinoderms that lived only in the Middle Cambrian epoch. Homostelea is a junior synonym. The classification of cinctans is controversial, but they are probably part of the echinoderm stem group. Cinctans were sessile, asymmetrical animals with a skeleton made of stereom plates and a racquet-shaped body composed of a theca and stele. They may have had a lifestyle similar to modern tunicates, filter-feeding by pumping water through gill slits in their pharynx. Description Cinctans were asymmetrical animals, though some species were nearly bilaterally symmetrical. Like all echinoderms, cinctans have a skeleton made of plates of stereom. The body of cinctans was divided into two sections, the main body, called the theca, and a posterior appendage called a stele. The overall shape of cinctans has been compared to a tennis racquet. The theca of cinctans was surrounded on its margins by a frame of large stereom plates called a cinctus, and the dorsal and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Miaolingian
The Miaolingian is the third Series of the Cambrian Period, and was formally named in 2018. It lasted from about to million years ago and is divided in ascending order into 3 stages: the Wuliuan, Drumian, and Guzhangian. The Miaolingian is preceded by the unnamed Cambrian Series 2 and succeeded by the Furongian series. It is named after the Miaoling Mountains in southeastern Guizhou Province, China. Definition A number of proposals for fossils and type sections were made before it was formally ratified in 2018. The most promising fossil markers were seen to be the respective first appearances of either trilobite species ''Ovatoryctocara granulata'' or ''Oryctocephalus indicus'', which both have an age close to million years ago. After some deliberation, the FAD of ''Oryctocephalus indicus'' was chosen to be the lower boundary marker, and the GSSP was placed in the Kaili Formation, Wuliu-Zengjiayan, Guizhou, China. The Miaolingian-Furongian boundary has the same definition a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wuliuan
The Wuliuan stage is the fifth stage of the Cambrian, and the first stage of the Miaolingian Series of the Cambrian. It was formally defined by the International Commission on Stratigraphy in 2018. Its base is defined by the first appearance of the trilobite species '' Oryctocephalus indicus''; it ends with the beginning of the Drumian Stage, marked by the first appearance of the trilobite '' Ptychagnostus atavus'' around million years ago. The 'golden spike' that formally defines the base of the age is driven into the Wuliu-Zengjiayan (乌溜-曾家崖) section of the Kaili formation, near Balang Village in the Miaoling Mountains, Guizhou, China. GSSP Three sections were discussed as GSSP candidates: the Wuliu-Zengjiayan section near Balang in Guizhou province (China), a section on Split Mountain in Nevada (USA) and the "Molodo river section" along the Molodo river (Sakha Republic, Russia). The Wuliu-Zengjiayan section is an outcrop of the Kaili Formation in the Wuliu quarr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mansilla Formation
Mansilla may refer to: *Mansilla (surname), a Spanish surname *Mansilla de la Sierra, a place in Spain *Mansilla de las Mulas, a place in Spain *Mansilla Mayor, a place in Spain *Gobernador Mansilla Gobernador Mansilla is a village and municipality in Entre Ríos Province in north-eastern Argentina Argentina, officially the Argentine Republic, is a country in the southern half of South America. It covers an area of , making it the Li ..., a place in Argentina See also * Mansilla + Tuñón Architects, a Spanish architecture firm {{disambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Province Of Zaragoza
Zaragoza (), also called Saragossa in English,''Encyclopædia Britannica''Zaragoza (conventional Saragossa)/ref> is a province of northern Spain, in the central part of the autonomous community of Aragon. Its capital is the city of Zaragoza, which is also the capital of the autonomous community. Other towns in the province include La Almunia de Doña Godina, Borja, Calatayud, Caspe, Ejea de los Caballeros, Tarazona, and Utebo. Its area is 17,274 km², which makes it the fourth-largest Spanish province by land area. Its population was 954,811 in 2018, accounting for slightly over 72% of the entire population of Aragon; nearly 75% of those lived in the capital. Its population density was 51/km². It contains 292 municipalities, of which more than half are villages with fewer than 300 people. The main language throughout the province is Spanish (with official status), although Catalan is spoken in the easternmost part ( Bajo Aragón-Caspe comarca and Mequinenza municipality ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pharyngeal Slit
Pharyngeal slits are Filter feeder, filter-feeding organs found among deuterostomes. Pharyngeal slits are repeated openings that appear along the pharynx caudal to the mouth. With this position, they allow for the movement of water in the mouth and out the pharyngeal slits. It is postulated that this is how pharyngeal slits first assisted in filter-feeding, and later, with the addition of gills along their walls, aided in respiration of aquatic chordates. These repeated segments are controlled by similar developmental mechanisms. Some hemichordate species can have as many as 200 gill slits. Pharynx, Pharyngeal clefts resembling gill slits are transiently present during the embryonic stages of tetrapod development. The presence of pharyngeal arches and clefts in the neck of the developing human embryo famously led Ernst Haeckel to postulate that "ontogeny recapitulates phylogeny"; this hypothesis, while false, contains elements of truth, as explored by Stephen Jay Gould in ''Onto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Filter Feeder
Filter feeders are aquatic animals that acquire nutrients by feeding on organic matters, food particles or smaller organisms (bacteria, microalgae and zooplanktons) suspended in water, typically by having the water pass over or through a specialized filtering organ that sieves out and/or traps solids. Filter feeders can play an important role in condensing biomass and removing excess nutrients (such as nitrogen and phosphate) from the local waterbody, and are therefore considered water-cleaning ecosystem engineers. They are also important in bioaccumulation and, as a result, as indicator organisms. Filter feeders can be sessile, planktonic, nektonic or even neustonic (in the case of the buoy barnacle) depending on the species and the niches they have evolved to occupy. Extant species that rely on such method of feeding encompass numerous phyla, including poriferans ( sponges), cnidarians (jellyfish, sea pens and corals), arthropods ( krill, mysids and barna ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carboniferous Echinoderms
The Carboniferous ( ) is a geologic period and system of the Paleozoic era that spans 60 million years, from the end of the Devonian Period Ma (million years ago) to the beginning of the Permian Period, Ma. It is the fifth and penultimate period of the Paleozoic era and the fifth period of the Phanerozoic eon. In North America, the Carboniferous is often treated as two separate geological periods, the earlier Mississippian and the later Pennsylvanian. The name ''Carboniferous'' means "coal-bearing", from the Latin ("coal") and ("bear, carry"), and refers to the many coal beds formed globally during that time. The first of the modern "system" names, it was coined by geologists William Conybeare and William Phillips in 1822, based on a study of the British rock succession. Carboniferous is the period during which both terrestrial animal and land plant life was well established. Stegocephalia (four-limbed vertebrates including true tetrapods), whose forerunners (tetrapodomor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
