| Austromarrella Temporal range: Middle Cambrian | |
|---|---|
 | |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Class: | † Marrellomorpha |
| Genus: | † Austromarrella Haug et al., 2012 |
| Type species | |
| †Austromarrella klausmuelleri Haug et al., 2012 | |
Austromarrella is an extinct genus of marrellomorph arthropod known from the Middle Cambrian (late Templetonian to early Floran) of Australia. [1]
The Cambrian Period was the first geological period of the Paleozoic Era, and of the Phanerozoic Eon. The Cambrian lasted 55.6 million years from the end of the preceding Ediacaran Period 541 million years ago (mya) to the beginning of the Ordovician Period 485.4 mya. Its subdivisions, and its base, are somewhat in flux. The period was established as "Cambrian series" by Adam Sedgwick, who named it after Cambria, the Latin name for 'Cymru' (Wales), where Britain's Cambrian rocks are best exposed. The Cambrian is unique in its unusually high proportion of lagerstätte sedimentary deposits, sites of exceptional preservation where "soft" parts of organisms are preserved as well as their more resistant shells. As a result, our understanding of the Cambrian biology surpasses that of some later periods.
The PaleozoicEra is the earliest of three geologic eras of the Phanerozoic Eon. It is the longest of the Phanerozoic eras, lasting from 541 to 251.902 million years ago, and is subdivided into six geologic periods : the Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian. The Paleozoic comes after the Neoproterozoic Era of the Proterozoic Eon and is followed by the Mesozoic Era.
The lobopodians, members of the informal group Lobopodia, or the formally erected phylum Lobopoda Cavalier-Smith (1998), are panarthropods with stubby legs called lobopods, a term which may also be used as a common name of this group as well. While the definition of lobopodians may differ between literatures, it usually refers to a group of soft-bodied, worm-like fossil panarthropods such as Aysheaia and Hallucigenia.
Opabinia regalis is an extinct, stem group arthropod found in the Middle Cambrian Burgess Shale Lagerstätte of British Columbia, Canada. It flourished from 505 million years ago to 487 million years ago during the Cambrian Period of the Paleozoic Era. It measured 2-3 inches in length and is presumed to have been a carnivore. Fewer than twenty good specimens have been described; 3 specimens of Opabinia are known from the Greater Phyllopod bed, where they constitute less than 0.1% of the community. Opabinia was a soft-bodied animal, averaging about 5.7 cm in length, and its segmented body had lobes along the sides and a fan-shaped tail. The head shows unusual features: five eyes, a mouth under the head and facing backwards, and a proboscis that probably passed food to the mouth. Opabinia probably lived on the seafloor, using the proboscis to seek out small, soft food.
Marrella is an extinct genus of arthropod known from the middle Cambrian Burgess Shale of British Columbia. It is the most common animal represented in the Burgess Shale.
The Emu Bay Shale is a geological formation in Emu Bay, South Australia, containing a major Konservat-Lagerstätte. 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.
Aglaspidida is an extinct order of aquatic arthropods that were once regarded as primitive chelicerates. However, anatomical comparisons demonstrate that the aglaspidids cannot be accommodated within the chelicerates, and that they lie instead within the Artiopoda, thus placing them closer to the trilobites. Aglaspidida contains the subgroups Aglaspididae and Tremaglaspididae, which are distinguished by the presence of acute/spinose genal angles and a long spiniform tailspine in the Aglaspididae.
Parapeytoia was a prehistoric animal that lived over 530 million years ago in the Maotianshan shales of prehistoric China. It was interpreted as an anomalocaridid (radiodont) with legs, but later studies reveal it was a megacheiran, a group of arthropods which are no longer thought to be closely related to the radiodonts.
Euthycarcinoidea are an enigmatic group of extinct possibly amphibious arthropods that ranged from Cambrian to Triassic times. Fossils are known from Europe, North America, Argentina, Australia and Antarctica.
Sarotrocercus is a small Cambrian organism known from Burgess shale-type localities, reaching a centimetre or two in length (0.39–0.79 in). It was pelagic and swam on its back. 28 specimens of Sarotrocercus are known from the Greater Phyllopod bed, where they comprise < 0.1% of the community. It may lie in the arthropod crown group, and a recent study has revised some points of its original description.
An arthropod is an invertebrate animal having an exoskeleton, a segmented body, and paired jointed appendages. Arthropods form the phylum Euarthropoda, which includes insects, arachnids, myriapods, and crustaceans. The term Arthropoda as originally proposed refers to a proposed grouping of Euarthropods and the phylum Onychophora. They are distinguished by their jointed limbs and cuticle made of chitin, often mineralised with calcium carbonate. The arthropod body plan consists of segments, each with a pair of appendages. In order to keep growing, they have to go through moulting, which sheds their skin. Arthropods are bilaterally symmetrical and their body possesses an external skeleton. Some species have wings. They are an extremely diverse group, with up to 10 million species.
Megacheira is an extinct class of predatory arthropods that possessed a pair of great appendages, hence the class name as well as the common name "great appendage arthropods". Their neural structures and deutocerebral appendages resemble those of chelicerates. Most of them were found in marine environments throughout the world from the lower to middle Cambrian. Megacheirans were important components of several faunas, including the Burgess, Wheeler and Maotianshan Shales Lagerstatten.
Class Xenusia, the Xenusiids, represents the subset of lobopodian worms that fall in the stem-lineage of Onychophora. Their type genus is Xenusion. They have relatively large, annulated, cylindrical bodies. Their lobopod legs have tubercles at their bases. Some have large frontal appendages, although these may represent taphonomic artefacts. Their mouth is terminal or subterminal, and they are marine. They probably represent a grade rather than a clade.
Jiucunella is genus of Cambrian arthropod known from the Cambrian Chengjiang biota of China as well as Australia.
Radiodonta is an order of stem-group arthropods that was successful worldwide during the Cambrian period, and included the earliest large predators known. They may be referred to as radiodonts, radiodontans, radiodontids, anomalocarids, or anomalocaridids, although the latter originally refer to the family Anomalocarididae, which previously included all species of this order but is now restricted to only a few species. Some of the most famous species of radiodonts are the Cambrian taxa Anomalocaris canadensis, Hurdia victoria, Peytoia nathorsti, and Amplectobelua symbrachiata, the Ordovician Aegirocassis benmoulai and the Devonian Schinderhannes bartelsi.
Great appendages are claw-like appendages which attach to the heads of the "great appendage arthropods", a name usually refers to Megacheira, a class of extinct arthropod characterized by a pair of "short-great appendages" bearing in front of the animal's head.
Skara is a genus of maxillopod crustacean known from the Upper Cambrian Orsten deposit of Sweden and similarly aged deposits in China. It is the only genus in the order Skaracarida and family Skaraidae, and contains three species:
Orstenoloricus is a loriciferan larva, presumably from the stem group, preserved by early three-dimensional mineralization in an orsten-type setting in the mid-Cambrian of Australia. It somewhat resembles the larva of the unusual loriciferan Tenuiloricus.
This list of fossil arthropods described in 2016 is a list of new taxa of trilobites, fossil insects, crustaceans, arachnids and other fossil arthropods of every kind that have been described during the year 2016, as well as other significant discoveries and events related to arthropod paleontology that occurred in the year 2016.
This list of fossil arthropods described in 2017 is a list of new taxa of trilobites, fossil insects, crustaceans, arachnids and other fossil arthropods of every kind that are scheduled to be described during the year 2017, as well as other significant discoveries and events related to arthropod paleontology that are scheduled to occur in the year 2017.
 | This prehistoric arthropod-related article is a stub. You can help Wikipedia by expanding it. |
