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Artiopoda
The Artiopoda is a grouping of extinct arthropods that includes trilobites and their close relatives. It was erected by Hou and Bergström in 1997 to encompass a wide diversity of arthropods that would traditionally have been assigned to the Trilobitomorpha. Hou and Bergström used the name Lamellipedia as a superclass to replace Trilobitomorpha that was originally erected at the subphylum level, which they considered inappropriate. Trilobites, in part due to their mineralising exoskeletons, are by far the most diverse and long lived members of the clade, with most records of other members, which lack mineralised exoskeletons, being from Cambrian deposits. Description According to Stein and Selden (2012) artiopods are recognised by the possession of filiform antennulae, limbs with bilobate exopods, with the proximal lobe being elongate and bearing a lamella, while the distal lobe is paddle-shaped and setiforous (bearing hair-or bristle like structures). The limb endopod has se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trilobita
Trilobites (; meaning "three lobes") are extinction, extinct marine arthropods that form the class (biology), class Trilobita. Trilobites form one of the earliest-known groups of arthropods. The first appearance of trilobites in the fossil record defines the base of the Atdabanian Stage (geology), stage of the Early Cambrian Period (geology), period () and they flourished throughout the lower Paleozoic before slipping into a long decline, when, during the Devonian, all trilobite orders except the Proetida died out. The last extant trilobites finally disappeared in Permian–Triassic extinction event, the mass extinction at the end of the Permian about 252 million years ago. Trilobites were among the most successful of all early animals, existing in oceans for almost 270 million years, with over 22,000 species having been described. By the time trilobites first appeared in the fossil record, they were already highly diversified and geographically dispersed. Because trilobites had ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retifacies
''Retifacies'' (''Retifacies abnormalis'') is an extinct arthropod, that lived in the lower Cambrian (about 518 million years ago). Its fossil remains have been found in the Maotianshan Shales of Yunnan, China. It is a member of the Artiopoda. Description This large animal could reach 55 centimeters in length, even though most of the specimens found were smaller. The cephalic shield was short, and was followed by a dozen tergites that overlapped each other. The rear part of the body consisted of a large shield and a long segmented tail. All the tergites had a surface made up of irregular polygons, unknown among other Maotianshan arthropods. Ventrally there were probably no eyes placed on peduncles, and immediately alongside there were two long antennae with short bristles. Like many primitive arthropods, this animal also had the classic biramous appendages, eighteen pairs in number. Three of these were positioned under the head, ten corresponded to the thoracic wipes and five ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acanthomeridion
''Acanthomeridion'' is an extinct arthropod found in the Chengjiang fauna deposits of China. In 1997, it was placed in its own, monotypic family, Acanthomeridiidae. It is known from eight specimens, all found in China. Morphology ''Acanthomeridion'' was a 35 mm-long animal, with 11 segments ending in rear-facing spines. The head features free cheeks separated from the rest of the head by sutures. This is analogous with trilobites. Otherwise, affinities are mainly unclear. More recently discovered specimens of the species ''Acanthomeridion anacanthus'' have paired gut diverticula as have been seen in artiopods. No fossils exposing the limbs have yet been found, but they are thought to be biramous with the upper section of the limb holding the gills. As limbs have not been found, it is uncertain whether ''Acanthomeridion'' was a seafloor-dweller or a swimmer. The streamlining suggests that it swam, but is inconclusive. Taxonomy ''Acanthomeridion'' is considered a primitiv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bailongia
''Bailongia'' is an extinct genus of arthropod known from a single species ''Bailongia longicaudata'' (''longicaudata'' from Latin: "long-tailed") found in the Cambrian Stage 4 aged Guanshan Biota of Yunnan, China. It was around 5mm long and had a large head shield, nine overlapping tapering tergites and a relatively elongate tailspine. It has been recovered in a relatively basal position within Artiopoda The Artiopoda is a grouping of extinct arthropods that includes trilobites and their close relatives. It was erected by Hou and Bergström in 1997 to encompass a wide diversity of arthropods that would traditionally have been assigned to the Trilo ..., more derived than '' Squamacula'' or Protosutura, but outside Trilobitomorpha or Vicissicaudata. Phylogeny After Jiao et al. 2021. References Artiopoda Cambrian arthropods of Asia Cambrian China Paleontology in Yunnan Fossil taxa described in 2021 Cambrian genus extinctions {{Paleo-arthropod-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cindarella
''Cindarella'' is genus of trilobite-like Cambrian arthropod known from the Chengjiang biota of China. It is classified in the stem group of trilobites (Artiopoda) in the clade Xandarellida, along with ''Phytophilaspis'', ''Sinoburius'', and ''Xandarella''. See also * Arthropod * Cambrian explosion * Chengjiang biota ** List of Chengjiang Biota species by phylum * Cinderella "Cinderella",; french: link=no, Cendrillon; german: link=no, Aschenputtel) or "The Little Glass Slipper", is a folk tale with thousands of variants throughout the world.Dundes, Alan. Cinderella, a Casebook. Madison, Wis: University of Wisconsi ... References External linksTrilobite Systematic Relationships Cambrian arthropods Maotianshan shales fossils Artiopoda {{paleo-arthropod-stub Cambrian genus extinctions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tegopelte
''Tegopelte gigas'' (from the Greek tegos, “tile,” and pelte, “leather-shield,” referring to the shape of the dorsal body covering; gigas – from the Greek gigas, “giant,” due to the huge size of the animalTegopelte gigas. A giant trilobite-like arthropod The Burgess Shale.) is a species of large (1 complete specimen was 27 cm) soft-bodied known from two specimens from the . |
Kuamaia
''Kuamaia'' is an extinct genus of artiopodan in the phylum Arthropoda. Fossils of the type species ''K. lata'' were discovered in the Chengjiang biota. The other species in the genus,''K. muricata'' has also been identified there, but neither species has been found elsewhere. ''Kuamaia lata'' was a benthic arthropod and a mobile hunter and scavenger. A spiny section on ''K. lata'''s legs is presumed to have allowed it to tear apart food. Morphology ''Kuamaia lata'' has an oval dorsal exoskeleton shape, with a gradual decline from the somewhat elevated medial axis of the animal to the exoskeleton edge. ''K. lata'' appears smooth, with little space between tergites and low-profile pleural spines. Some fusion of parts of the exoskeleton is evident, but there is some discussion as to what degree this occurred. The tail segment has three more prominent spines, two being lateral and one axial. The largest fossil ''K. lata'' was at least 10 cm long, excluding appendages. On th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phytophilaspis
''Phytophilaspis'' is a phosphatized genus of trilobite-like arthropod with eyes, found in association with algal remains. It dwelt in well-lit, shallow waters. Description ''Phytophilaspis'' has several features in common with trilobites, including: tripartite division of the dorsal shield; presence of prominent pygidium; large eyes, situated on the pleural area of the cephalon; facial sutures, and shape of the hypostome. However, it differs from trilobites in many ways, including a reduced thorax, thoracic pleura fused to each other and to the cephalon and pygidium, facial sutures not crossing the eyes, and weak original mineralization of the cuticle. Because of these differences, ''Phytophilaspis'' was originally assigned to the Artiopodan subclass Concilliterga, in an undetermined order and family. It was later considered by Bergström and Hou as a xandarellid, along with ''Cindarella'', ''Xandarella'' and ''Sinoburius''. A position that was supported in subsequent studies. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nektaspida
Nektaspida (also called Naraoiida, Nektaspia and Nectaspida) is an extinct order of non- mineralised artiopodan arthropods. They are known from the mid-Cambrian to the upper Silurian. Originally classified as trilobites, which they superficially resemble, they are now placed as close relatives as members of the Trilobitomorpha within Artiopoda. The order is divided into three major families; Emucarididae, Liwiidae, and Naraoiidae. Naming history and taxonomic placement The order was originally proposed by Raymond in 1920 as Nektaspia. Størmer corrected it to Nectaspida for the 1959 ''Treatise on Invertebrate Paleontology'' to conform with the names of the other trilobite orders. Whittington described it in 1985 with the spelling Nektaspida; the revised 1997 Treatise by Raymond and Fortey uses this spelling, as do other modern works. Whittington (1985) placed the order in the Trilobita. Cotton & Braddy (2000) place it in a new "Trilobite clade" containing the Trilobita, recogni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthroaspis
''Arthroaspis'' is an extinct genus of arthropod known from the Cambrian aged Sirius Passet Lagerstatte in Greenland. It is relatively large in size for Cambrian arthropods, attaining a length of up to 215 mm. It is a common component of the Passet fauna, being located at multiple localities within the formation. It possessed 14 tergites. In the describing paper, it was recovered as a member of a non-monophyletic Artiopoda The Artiopoda is a grouping of extinct arthropods that includes trilobites and their close relatives. It was erected by Hou and Bergström in 1997 to encompass a wide diversity of arthropods that would traditionally have been assigned to the Trilo .... It has subsequently been considered a potential close relative of nektaspids. References {{Taxonbar, from=Q96372401 Artiopoda ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sidneyia
''Sidneyia'' is an extinct arthropod known from fossils found from the Early Cambrian-age Maotianshan Shales to the Mid Cambrian Burgess Shale formation of British Columbia. 144 specimens of ''Sidneyia'' are known from the Greater Phyllopod bed, where they comprise 0.27% of the community. General description ''Sidneyia'' ranged from in length and is one of the largest arthropods found at the site. It is thought to have been a benthic carnivore and scavenger that walked along the sea floor in search of hard-shelled prey. Gut contents have revealed that ''Sidneyia'' fed largely on small trilobites, as well as on brachiopods, hyoliths and small arthropods. The gut was narrow, but widens posteriorly to form a pocket where digestion presumably took place. The retention of feces likely indicates infrequent feeding Its exquisitely preserved gnathobases resemble those of ''Limulus'', and were probably used to crush prey. ''Sidneyia'' was discovered in 1910 during the first day of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Falcatamacaris
''Falcatamacaris'' is an extinct genus of Cambrian artiopodan arthropod, only known from the type species ''F. bellua'' described in 2014, from the Guzhangian (Cambrian Stage 3) aged Weeks Formation in Utah. The holotype specimen is over 10 cm long (not including the absent telson). The trunk consists of 11 tergites A ''tergum'' (Latin for "the back"; plural ''terga'', associated adjective tergal) is the dorsal ('upper') portion of an arthropod segment other than the head. The anterior edge is called the 'base' and posterior edge is called the 'apex' or 'mar ..., with crescent shaped pleural spines. Its placement within the Artiopoda was unresolved. References Artiopoda {{Paleo-arthropod-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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