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Eocarcinus
''Eocarcinus praecursor'' is a Jurassic species of decapod crustacean, sufficiently distinct from its relatives to be placed in its own family (Eocarcinidae). Often considered the oldest true crab, it was considered by a 2010 study to be an early member of the Anomura. However, a reanalysis in 2020 again found it to be the earliest known stem-group crab. Distribution It lived during the early Pliensbachian age (Lower Jurassic), and has been found in rocks at two sites in the United Kingdom – Mickelton Tunnel (near Aston Magna), Gloucestershire and Runswick Bay, Yorkshire. Description In many of its characters, it represents a transitional stage between the Glypheoidea and the Middle Jurassic crabs in the Prosopidae. Since its ancestors were long-tailed decapods, and its successors were short-tailed crabs, ''Eocarcinus'' has been described as "the lobster who decided to become a crab". Previously considered to be the oldest known true crab, a 2010 revision concluded that '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eocarcinus Reconstructon
''Eocarcinus praecursor'' is a Jurassic species of decapod crustacean, sufficiently distinct from its relatives to be placed in its own family (Eocarcinidae). Often considered the oldest true crab, it was considered by a 2010 study to be an early member of the Anomura. However, a reanalysis in 2020 again found it to be the earliest known stem-group crab. Distribution It lived during the early Pliensbachian age (Lower Jurassic), and has been found in rocks at two sites in the United Kingdom – Mickelton Tunnel (near Aston Magna), Gloucestershire and Runswick Bay, Yorkshire. Description In many of its characters, it represents a transitional stage between the Glypheoidea and the Middle Jurassic crabs in the Prosopidae. Since its ancestors were long-tailed decapods, and its successors were short-tailed crabs, ''Eocarcinus'' has been described as "the lobster who decided to become a crab". Previously considered to be the oldest known true crab, a 2010 revision concluded that '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eocarcinus Fossil2
''Eocarcinus praecursor'' is a Jurassic species of decapod crustacean, sufficiently distinct from its relatives to be placed in its own family (Eocarcinidae). Often considered the oldest true crab, it was considered by a 2010 study to be an early member of the Anomura. However, a reanalysis in 2020 again found it to be the earliest known stem-group crab. Distribution It lived during the early Pliensbachian age (Lower Jurassic), and has been found in rocks at two sites in the United Kingdom – Mickelton Tunnel (near Aston Magna), Gloucestershire and Runswick Bay, Yorkshire. Description In many of its characters, it represents a transitional stage between the Glypheoidea and the Middle Jurassic crabs in the Prosopidae. Since its ancestors were long-tailed decapods, and its successors were short-tailed crabs, ''Eocarcinus'' has been described as "the lobster who decided to become a crab". Previously considered to be the oldest known true crab, a 2010 revision concluded that '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crab
Crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" (abdomen) ( el, βραχύς , translit=brachys = short, / = tail), usually hidden entirely under the thorax. They live in all the world's oceans, in freshwater, and on land, are generally covered with a thick exoskeleton, and have a single pair of pincers. They first appeared during the Jurassic Period. Description Crabs are generally covered with a thick exoskeleton, composed primarily of highly mineralized chitin, and armed with a pair of chelae (claws). Crabs vary in size from the pea crab, a few millimeters wide, to the Japanese spider crab, with a leg span up to . Several other groups of crustaceans with similar appearances – such as king crabs and porcelain crabs – are not true crabs, but have evolved features similar to true crabs through a process known as carcinisation. Environment Crabs are found in all of the world's oceans, as well as in fresh w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jurassic
The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The Jurassic constitutes the middle period of the Mesozoic, Mesozoic Era and is named after the Jura Mountains, where limestone strata from the period were first identified. The start of the Jurassic was marked by the major Triassic–Jurassic extinction event, associated with the eruption of the Central Atlantic magmatic province, Central Atlantic Magmatic Province. The beginning of the Toarcian Stage started around 183 million years ago and is marked by an extinction event associated with widespread Anoxic event, oceanic anoxia, ocean acidification, and elevated temperatures likely caused by the eruption of the Karoo-Ferrar, Karoo-Ferrar large igneous provinces. The end of the Jurassic, however, has no clear boundary with the Cretaceous and i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anomura
Anomura (sometimes Anomala) is a group of Decapoda, decapod crustaceans, including hermit crabs and others. Although the names of many anomurans include the word ''crab'', all true crabs are in the sister group to the Anomura, the Brachyura (the two groups together form the clade Meiura). Description The name Anomura derives from an old classification in which Reptantia, reptant decapods were divided into Macrura (long-tailed), Brachyura (short-tailed) and Anomura (differently-tailed). The alternative name Anomala reflects the unusual variety of forms in this group; whereas all crabs share some obvious similarities, the various groups of anomurans are quite dissimilar. The group has been moulded by several instances of carcinisation – the development of a crab-like body form. Thus, the king crabs (Lithodidae), porcelain crabs (Porcellanidae) and hairy stone crab (Lomisidae) are all separate instances of carcinisation. As decapods (meaning ''ten-legged''), anomurans have ten pe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Animal
Animals are multicellular, eukaryotic organisms in the Kingdom (biology), biological kingdom Animalia. With few exceptions, animals Heterotroph, consume organic material, Cellular respiration#Aerobic respiration, breathe oxygen, are Motility, able to move, can Sexual reproduction, reproduce sexually, and go through an ontogenetic stage in which their body consists of a hollow sphere of Cell (biology), cells, the blastula, during Embryogenesis, embryonic development. Over 1.5 million Extant taxon, living animal species have been Species description, described—of which around 1 million are Insecta, insects—but it has been estimated there are over 7 million animal species in total. Animals range in length from to . They have Ecology, complex interactions with each other and their environments, forming intricate food webs. The scientific study of animals is known as zoology. Most living animal species are in Bilateria, a clade whose members have a Symmetry in biology#Bilate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zoosystema
''Zoosystema'' is a peer-reviewed scientific journal published by the National Museum of Natural History, France (''Muséum national d'histoire naturelle''), covering research in animal biodiversity. Specific subjects within the journal's scope include comparative, functional and evolutionary morphology, phylogeny, biogeography, taxonomy and nomenclature, among others. Zoosystema publishes articles in English and French. Indexing The journal is abstracted and indexed by Current Contents, Biological Abstracts, ASFA (Aquatic Sciences and Fisheries Abstracts), Pascal, Zoological Record, Journal Citation Index Expanded (SciSearch®) and Scopus Scopus is Elsevier's abstract and citation database launched in 2004. Scopus covers nearly 36,377 titles (22,794 active titles and 13,583 inactive titles) from approximately 11,678 publishers, of which 34,346 are peer-reviewed journals in top-l .... References {{reflist Zoology journals Animal science journals Open access journals Ac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gloucestershire
Gloucestershire ( abbreviated Glos) is a county in South West England. The county comprises part of the Cotswold Hills, part of the flat fertile valley of the River Severn and the entire Forest of Dean. The county town is the city of Gloucester and other principal towns and villages include Cheltenham, Cirencester, Kingswood, Bradley Stoke, Stroud, Thornbury, Yate, Tewkesbury, Bishop's Cleeve, Churchdown, Brockworth, Winchcombe, Dursley, Cam, Berkeley, Wotton-under-Edge, Tetbury, Moreton-in-Marsh, Fairford, Lechlade, Northleach, Stow-on-the-Wold, Chipping Campden, Bourton-on-the-Water, Stonehouse, Nailsworth, Minchinhampton, Painswick, Winterbourne, Frampton Cotterell, Coleford, Cinderford, Lydney and Rodborough and Cainscross that are within Stroud's urban area. Gloucestershire borders Herefordshire to the north-west, Worcestershire to the north, Warwickshire to the north-east, Oxfordshire to the east, Wiltshire to the south, Bristol and Somerset ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Runswick Bay
Runswick Bay is a bay in the Scarborough Borough of North Yorkshire, England. It is also the name of a village located on the western edge of the bay (although the village is sometimes shortened to Runswick on UK road signs). It is north of Whitby, and close to the villages of Ellerby and Hinderwell. It is a popular tourist attraction due to its picturesque cliffside village, stunning coastal walks, fossil hunting and ''Runswick Sands'', a white sand beach. It is on the Cleveland Way national trail. Runswick Bay was chosen as Beach of the Year 2020 by ''The Sunday Times''. History The original fishing village was almost completely destroyed by a landslide in 1682. Remarkably, there were no fatalities, as the village was alerted by two mourners at a wake. The village was rebuilt, slightly further to the south, perched on the side of cliffs. The village ran its own lifeboat from 1866, until it was moved to the RNLI station at Staithes in 1978. The boathouse still rem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yorkshire
Yorkshire ( ; abbreviated Yorks), formally known as the County of York, is a Historic counties of England, historic county in northern England and by far the largest in the United Kingdom. Because of its large area in comparison with other English counties, functions have been undertaken over time by its subdivisions, which have also been subject to History of local government in Yorkshire, periodic reform. Throughout these changes, Yorkshire has continued to be recognised as a geographic territory and cultural region. The name is familiar and well understood across the United Kingdom and is in common use in the media and the Yorkshire Regiment, military, and also features in the titles of current areas of civil administration such as North Yorkshire, South Yorkshire, West Yorkshire and the East Riding of Yorkshire. Within the borders of the historic county of Yorkshire are large stretches of countryside, including the Yorkshire Dales, North York Moors and Peak District nationa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glypheoidea
The Glypheoidea (containing the glypheoid lobsters), is a group of lobster-like decapod crustaceans which forms an important part of fossil faunas, such as the Solnhofen limestone. These fossils included taxa such as ''Glyphea'' (from which the group takes its name), and ''Mecochirus'', mostly with elongated (often semichelate) chelipeds. This group of decapods is a good example of a living fossil, or a lazarus taxon, since until their discovery in the 1970s, the group was considered to have become extinct in the Eocene. The superfamily Glypheoidea comprises five families. The two extant species, ''Neoglyphea inopinata'' and ''Laurentaeglyphea neocaledonica'', are both in the Glypheidae. Prehistoric abundance The first animals attributable to the Glypheoidea appeared in the Permo-Triassic. They were abundant in the Jurassic, but declined from the Cretaceous to the Eocene. Extant taxa The Glypheoidea was originally considered to be a purely fossil group. That opinion had to be a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transitional Fossil
A transitional fossil is any fossilized remains of a life form that exhibits traits common to both an ancestral group and its derived descendant group. This is especially important where the descendant group is sharply differentiated by gross anatomy and mode of living from the ancestral group. These fossils serve as a reminder that taxonomic divisions are human constructs that have been imposed in hindsight on a continuum of variation. Because of the incompleteness of the fossil record, there is usually no way to know exactly how close a transitional fossil is to the point of divergence. Therefore, it cannot be assumed that transitional fossils are direct ancestors of more recent groups, though they are frequently used as models for such ancestors. In 1859, when Charles Darwin's ''On the Origin of Species'' was first published, the fossil record was poorly known. Darwin described the perceived lack of transitional fossils as "the most obvious and gravest objection which can be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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