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Echidnacaris
''Echidnacaris briggsi'' is an extinct species of radiodont known from the Cambrian Stage 4 aged Emu Bay Shale of Australia. Formerly referred to as ''"Anomalocaris" briggsi'', it was placed in the new monotypic genus ''Echidnacaris'' in 2023. It is only distantly related to true ''Anomalocaris'', and is instead placed in the family Tamisiocarididae. ''Echidnacaris'' is primarily known from its frontal appendages which had 13 podomeres. The largest appendages measured up to long, which would have belonged to an individual measuring between long. The first few segments of the appendages were substantially taller than they were wide, with podomeres 2-12 bearing long, slender posteriorly curving endites/ventral spines which bore numerous small auxiliary spines. Like other tamisiocaridids, it is suggested to have been a suspension feeder, using its frontal appendages to capture small prey. Isolated eyes attributed to the species suggest that they were not stalked, but instead were ... [...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] |
Radiodont
Radiodonta is an extinct 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 canadensis'', '' Hurdia victoria'', ''Peytoia nathorsti'', '' Titanokorys gainesi, Cambroraster falcatus'' and '' 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 arrangement of tooth plates (oral cone) surrounding the mouth, although this feature is su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tamisiocarididae
Tamisiocarididae is a family of Radiodonta, radiodonts, extinct marine animals related to arthropods, that bore finely-spined appendages that were presumably used in filter-feeding. When first discovered, the clade was named Cetiocaridae after a speculative evolution artwork, ''Bearded Ceticaris'' by John Meszaros, that depicted a hypothetical filter-feeding radiodont at a time before any were known to exist. However, the family name was not valid according to the International Code of Zoological Nomenclature, as no real genus named "Cetiocaris" exists, and in 2019 it was formally replaced by the name Tamisiocarididae, after the only valid genus of the clade at the time. The family is only known from Cambrian Series 2, Series 2 of the Cambrian, unlike other radiodont families, which persisted longer into the Cambrian. All known species would have lived in tropical or subtropical waters, suggesting a preference for warmer waters. Description Like most radiodonts, cetiocarids have s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emu Bay Shale
The Emu Bay Shale is a Formation (stratigraphy), geological formation in Emu Bay, South Australia, containing a major Konservat-Lagerstätte (fossil beds with soft tissue preservation). It is one of two in the world containing Redlichiidan trilobites. The Emu Bay Shale is dated as Cambrian Series 2, Stage 4, correlated with the upper Botomian Stage of the Lower Cambrian. Its mode of preservation is Burgess shale type preservation, the same as the Burgess shale, but the larger grain size of the Emu Bay rock means that the quality of preservation is lower. More than 50 species of trilobites, non-biomineralized arthropods (including Megacheira, megacheirans, Nektaspida, nektaspids, and Hymenocarina, hymenocarines), Radiodonta, radiodonts, palaeoscolecids, a lobopodian, a polychaete, vetulicolians, Nectocarididae, nectocaridids, Hyolitha, hyoliths, brachiopods, sponges, Chancelloriidae, chancelloriids, several Incertae sedis, problematica and a Chelicerata, chelicerate are known from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anomalocaris
''Anomalocaris'' (from Ancient Greek , meaning "unlike", and , meaning "shrimp", with the intended meaning "unlike other shrimp") is an extinct genus of radiodont, an order of early-diverging stem-group marine arthropods. It is best known from the type species ''A. canadensis,'' found in the Stephen Formation (particularly the Burgess Shale) of British Columbia, Canada. The other named species ''A. daleyae'' is known from the somewhat older Emu Bay Shale of Australia. Other unnamed ''Anomalocaris'' species are known from China and the United States. Like other radiodonts, ''Anomalocaris'' had swimming flaps running along its body, large compound eyes, and a single pair of segmented, frontal appendages, which in ''Anomalocaris'' were used to grasp prey. Estimated to reach long excluding the frontal appendages and tail fan, ''Anomalocaris'' is one of the largest animals of the Cambrian, and thought to be one of the earliest examples of an apex predator, though others have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cambrian Stage 4
Cambrian Stage 4 is the still unnamed fourth stage of the Cambrian and the upper stage of Cambrian Series 2. It follows Cambrian Stage 3 and lies below the Wuliuan. The lower boundary has not been formally defined by the International Commission on Stratigraphy. One proposal is the first appearance of two trilobite genera, '' Olenellus'' or ''Redlichia''. Another proposal is the first appearance of the trilobite species '' Arthricocephalus chauveaui''. Both proposals will set the lower boundary close to million years ago. The upper boundary corresponds to the beginning of the Wuliuan. Naming The International Commission on Stratigraphy has not named the fourth stage of the Cambrian yet. In the widely used Siberian nomenclature stage 4 would overlap with parts of the Botomian and Toyonian. Biostratigraphy The beginning of Cambrian Stage 4 has been tentatively correlated with the base of the European Leonian faunal stage and the base of the South China Duyunian faunal stage. Durin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Australia
Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller islands. It has a total area of , making it the list of countries and dependencies by area, sixth-largest country in the world and the largest in Oceania. Australia is the world's flattest and driest inhabited continent. It is a megadiverse countries, megadiverse country, and its size gives it a wide variety of landscapes and Climate of Australia, climates including deserts of Australia, deserts in the Outback, interior and forests of Australia, tropical rainforests along the Eastern states of Australia, coast. The ancestors of Aboriginal Australians began arriving from south-east Asia 50,000 to 65,000 years ago, during the Last Glacial Period, last glacial period. By the time of British settlement, Aboriginal Australians spoke 250 distinct l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endite
The arthropod leg is a form of jointed appendage of arthropods, usually used for walking. Many of the terms used for arthropod leg segments (called podomeres) are of Latin origin, and may be confused with terms for bones: ''coxa'' (meaning hip, : ''coxae''), ''trochanter'', ''femur'' (: ''femora''), ''tibia'' (: ''tibiae''), ''tarsus'' (: ''tarsi''), ''ischium'' (: ''ischia''), ''metatarsus'', ''carpus'', ''dactylus'' (meaning finger), ''patella'' (: ''patellae''). Homologies of leg segments between groups are difficult to prove and are the source of much argument. Some authors posit up to eleven segments per leg for the most recent common ancestor of extant arthropods but modern arthropods have eight or fewer. It has been argued that the ancestral leg need not have been so complex, and that other events, such as successive loss of function of a ''Hox''-gene, could result in parallel gains of leg segments. In arthropods, each of the leg segments articulates with the next segmen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Suspension 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 barnacles), mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sclerotin
Sclerotin is a component of the cuticle of various Arthropoda, most familiarly insects. It is formed by cross-linking members of particular classes of protein molecules, a biochemical process called sclerotization, a form of tanning in which quinones are enzymatically introduced into the cuticle, and react with terminal and lysine-related amino groups in the proteins to form strong links between the molecules.Chapman, R.F. (1969) ''The Insects: Structure and Function''. Elsevier, New York. Chapter 22.37 - "Expansion of the new cuticle is brought to an end by the onset of tanning" The resulting material greatly increases the rigidity of an insect's chitinous exoskeleton, which is otherwise fairly soft. It is particularly prominent in the thicker, armoured parts of insect and arachnid Arachnids are arthropods in the Class (biology), class Arachnida () of the subphylum Chelicerata. Arachnida includes, among others, spiders, scorpions, ticks, mites, pseudoscorpions, opiliones, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cambrian Arthropods
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, Panthalassa Ocean. The assembly of Gondwana during the Ediacaran and early Cambrian led to the development of new Convergent boundary, convergent plate boundaries and Volcanic arc, 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, life on Earth; prior to the Period, the majority of living organisms were small, Unicellular organism, unicellular and poorly preserved. Complex, multicellular organisms gradually became more common during the Ediacaran, but it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossil Taxa Described In 2023
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] |
