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Lyrarapax Unguispinus
'' Lyrarapax'' is a radiodont genus of the family Amplectobeluidae that lived in the early Cambrian period 518 million years ago. Its fossils were found in the Maotianshan Shales of China. The first species, ''Lyrarapax unguispinus'' was described in 2014, with a second species, ''Lyrarapax trilobus'' being described in 2016, differing principally in the morphology of its frontal appendages. Description ''L. unguispinus'' is roughly long. Its frontal appendages are short with a large first endite bearing several spines and alternating endites thereafter. The neck is prominent with four segments. The first flap pair is hypertrophied and paddle-shaped, with the following pairs decreasing sharply in size and a tail fan composed of three blade-like flap pairs. Remarkably, the nervous system of ''L. unguispinus'' is preserved in detail, showing that radiodont frontal appendages are protocerebral like the antennae of velvet worms, showing the two structures derive from the same sour ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radiodonta
Radiodonta is an extinct Order (biology), order of stem-group arthropods that was successful worldwide during the Cambrian period. Radiodonts are distinguished by their distinctive frontal appendages, which are morphologically diverse and were used for a variety of functions. Radiodonts were among the earliest large predators, but they also included sediment sifters and filter feeders. Some of the most famous species of radiodonts are the Cambrian taxa ''Anomalocaris, Anomalocaris canadensis'', ''Hurdia, Hurdia victoria'', ''Peytoia nathorsti'', ''Titanokorys gainesii, Titanokorys gainesi, Cambroraster, Cambroraster falcatus'' and ''Amplectobelua, Amplectobelua symbrachiata''. The later surviving members include the subfamily Aegirocassisinae from the Early Ordovician of Morocco and the Early Devonian member ''Schinderhannes bartelsi'' from Germany. Etymology The name Radiodonta (Latin for ''radius'' "spoke of a wheel" and Greek for ''odoús'' "tooth") refers to the radial arrang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genus
Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus. :E.g. ''Panthera leo'' (lion) and ''Panthera onca'' (jaguar) are two species within the genus ''Panthera''. ''Panthera'' is a genus within the family Felidae. The composition of a genus is determined by taxonomy (biology), taxonomists. The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: # monophyly – all descendants of an ancestral taxon are grouped together (i.e. Phylogeneti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amplectobeluidae
''Amplectobeluidae'' is a clade of Cambrian radiodonts. It currently includes five definitive genera, ''Amplectobelua'', '' Lyrarapax'', '' Ramskoeldia'', '' Guanshancaris'' and a currently unnamed genus from the lower Cambrian aged Sirius Passet site in Greenland. There is also a potential fifth genus, ''Houcaris'', but that genus has become problematic in terms of its taxonomic placement. Definition In 2014, ''Amplectobeluidae'' was defined as the most inclusive clade including '' Amplectobelua symbrachiata'' but not ''Anomalocaris canadensis'', '' Tamisiocaris borealis'', or '' Hurdia victoria''. Description Amplectobeluids could be recognized by frontal appendages with well-developed first distal endite, which forming a pincer-like structure that presumably better suited for a grasping function. Complete body fossils of amplectobeluids are only known by ''Amplectobelua'' and '' Lyrarapax'', both showing combination of characters resembling ''Anomalocaris'' (i.e. streaml ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cambrian
The Cambrian ( ) is the first geological period of the Paleozoic Era, and the Phanerozoic Eon. The Cambrian lasted 51.95 million years from the end of the preceding Ediacaran period 538.8 Ma (million years ago) to the beginning of the Ordovician Period 486.85 Ma. Most of the continents lay in the southern hemisphere surrounded by the vast Panthalassa Ocean. The assembly of Gondwana during the Ediacaran and early Cambrian led to the development of new convergent plate boundaries and continental-margin arc magmatism along its margins that helped drive up global temperatures. Laurentia lay across the equator, separated from Gondwana by the opening Iapetus Ocean. The Cambrian marked a profound change in life on Earth; prior to the Period, the majority of living organisms were small, unicellular and poorly preserved. Complex, multicellular organisms gradually became more common during the Ediacaran, but it was not until the Cambrian that fossil diversity seems to rapidly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maotianshan Shales
The Maotianshan Shales () are a series of Early Cambrian sedimentary deposits in the Chiungchussu Formation or Heilinpu Formation, famous for their '' Konservat Lagerstätten'', deposits known for the exceptional preservation of fossilized organisms or traces. The Maotianshan Shales form one of some forty Cambrian fossil locations worldwide exhibiting exquisite preservation of rarely preserved, non-mineralized soft tissue, comparable to the fossils of the Burgess Shale of British Columbia, Canada. They take their name from Maotianshan Hill () in Chengjiang County, Yunnan Province, China. The most famous assemblage of organisms are referred to as the Chengjiang biota for the multiple scattered fossil sites in Chengjiang. The age of the Chengjiang Lagerstätte is locally termed Qiongzhusian, a stage correlated to the late Atdabanian Stage in Siberian sequences of the middle of the Early Cambrian. The shales date to ≤. Along with the Burgess Shale, the Maotianshan Shales ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Velvet Worm
Onychophora (from , , "claws"; and , , "to carry"), commonly known as velvet worms (for their velvety texture and somewhat wormlike appearance) or more ambiguously as peripatus (after the first described genus, '' Peripatus''), is a phylum of elongate, soft-bodied, many-legged animals. In appearance they have variously been compared to worms with legs, caterpillars, and slugs. They prey upon other invertebrates, which they catch by ejecting an adhesive slime. Approximately 200 species of velvet worms have been described, although the true number is likely to be much greater. The two extant families of velvet worms are Peripatidae and Peripatopsidae. They show a peculiar distribution, with the peripatids being predominantly equatorial and tropical, while the peripatopsids are all found south of the equator. It is the only phylum within Animalia that is wholly endemic to terrestrial environments, at least among extant members. Velvet worms are generally considered close relative ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Labrum (arthropod)
The labrum is a flap-like structure that lies immediately in front of the mouth in almost all extant Euarthropoda. The most conspicuous exceptions are the Pycnogonida, which are probably chelicerates. In entomology, the labrum amounts to the "upper lip" of an insect mouth, the corresponding "lower lip" being the labium. The evolutionary origin, embryogenesis, and morphological development of the labrum have proved to be some of the most controversial and challenging topics in the study of arthropod head structures. Embryonic nature and origin of the labrum The labrum is innervated in crustaceans and insects from the tritocerebrum (the back of the brain). However, in development, its embryonic primordium often appears at the anterior of the head and migrates backwards towards its adult position. Furthermore, it often appears as a bilobed structure, with a set of muscles, nerves and gene expression in many ways similar to that of an appendage. This evidence has been used to s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthropod Head Problem
The (pan)arthropod head problem is a long-standing zoological dispute concerning the Segmentation (biology), segmental composition of the heads of the various arthropod groups, and how they are evolutionarily related to each other. While the dispute has historically centered on the exact make-up of the insect head, it has been widened to include other living arthropods, such as chelicerates, myriapods, and crustaceans, as well as fossil forms, such as the many arthropods known from exceptionally preserved Cambrian faunas. While the topic has classically been based on insect embryology, in recent years a great deal of Evolutionary developmental biology, developmental molecular data has become available. Dozens of more or less distinct solutions to the problem, dating back to at least 1897, have been published, including several in the 2000s. The arthropod head problem is popularly known as the endless dispute, the title of a famous paper on the subject by Jacob G. Rempel in 1975, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lyre
The lyre () (from Greek λύρα and Latin ''lyra)'' is a string instrument, stringed musical instrument that is classified by Hornbostel–Sachs as a member of the History of lute-family instruments, lute family of instruments. In organology, a lyre is considered a yoke lute, since it is a lute in which the strings are attached to a yoke that lies in the same plane as the sound table, and consists of two arms and a crossbar. The lyre has its origins in ancient history. Lyres were used in several ancient cultures surrounding the Mediterranean Sea. The earliest known examples of the lyre have been recovered at archeological sites that date to c. 2700 BCE in Mesopotamia. The oldest lyres from the Fertile Crescent are known as the eastern lyres and are distinguished from other ancient lyres by their flat base. They have been found at archaeological sites in Egypt, Syria, Anatolia, and the Levant. In a discussion of the Nubian lyre, Carl Engel notes that modern Egyptians call it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleobiota Of The Maotianshan Shales
This is a list of fossils found at Maotianshan Shales, whose most famous assemblage of organisms are referred to as the Chengjiang biota. The Maotianshan Shales are a series of Cambrian, Early Cambrian Shale, sedimentary deposits in the Chiungchussu Formation, famous for their ''Lagerstätte, Konservat Lagerstätten'', deposits known for the exceptional preservation of fossilized organisms or Trace fossil, traces. The Maotianshan Shales form one of some forty Cambrian fossil locations worldwide exhibiting exquisite preservation of rarely preserved, non-mineralized soft tissue, comparable to the fossils of the Burgess Shale of British Columbia, Canada. Ecdysozoa Scalidophora Palaeoscolecid, Palaeoscolecidomorpha Priapulida Panarthropoda Lobopodia = Eoconchariidae = = Hallucishaniida, Hallucishaniids = = Lobopodia#Siberion_and_similar_taxa, Siberiidae = = Lobopodia#Gilled_lobopodians, Gilled Lobopodians = Radiodonta Radiodonta are a group of highly su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossils Of China
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Though the fossil record is incomplete, numerous studies have demonstrated that there is enough information available to give a good understanding of the pattern of diversification of life on Earth. In addition, the record can predict and fill gaps such as the discovery of ''Tiktaalik'' in the arctic of Canada. Paleontology includes the study of fossils: their age, method of formation, and evolutionary significance. Specimens are sometimes considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years to 4.1 billion years old. Early edition, published online before print. The ob ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossil Taxa Described In 2014
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Though the fossil record is incomplete, numerous studies have demonstrated that there is enough information available to give a good understanding of the pattern of diversification of life on Earth. In addition, the record can predict and fill gaps such as the discovery of ''Tiktaalik'' in the arctic of Canada. Paleontology includes the study of fossils: their age, method of formation, and evolutionary significance. Specimens are sometimes considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years to 4.1 billion years old. Early edition, published online before print. The o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
