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Carimersa Neptuni
''Carimersa'' is an extinct genus of artiopodan arthropod known from the Silurian Coalbrookdale Formation of Herefordshire, England. Description The body is flattened, and divided into the head with five pairs of paired appendages, the trunk with 10 appendage-bearing segments, a limbless abdomen with 4 segments, with the body terminating with tailspine. The total length of the body excluding the tailspine is around , with a max width of about . The first antennae-like head appendage bears three flagellae-like structures. The second and third head appendages are uniramous and have basipods (basal segments) modified into spined gnathobases (used to process food). The last two head appendages and the trunk limbs are biramous, and have robust endopods that bear spines, with the exopods being flap-like and reinforced by a rod-like structure. Ecology ''Carimersa'' was likely an actively swimming organism that probably swam close to the sediment surface. The presence of associat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Artiopoda
Artiopoda is a clade 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. Trilobites, in part due to abundance of findings owing to their mineralized exoskeletons, are by far the best recorded, diverse, and long lived members of the clade. Other members, which lack mineralised exoskeletons, are known mostly from 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 Ordov ... deposits. Description According to Stein and Selden (2012) artiopods are recognised by the possession of filiform antennulae, limbs with bilobate exopods (upper branches), with the proximal (closest to base of the limb) lobe being elong ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emeraldella
''Emeraldella'' is a genus of arthropod known from the Middle Cambrian of North America. The type species ''E. brocki'' was described in 1912 from the Burgess Shale. 21 specimens of ''Emeraldella'' are known from the Greater Phyllopod bed, where they comprise < 0.1% of the community. A re-study on the species was done in 2012. A second species ''E. brutoni'' is known from the Wheeler Shale, which was described in 2011. An additional specimen of ''E. brutoni'' was described in 2019, which revealed more of the anatomy. It has been placed as a basal member of the clade Vicissicaudata within Artiopoda, a group of arthropods containing trilobites and their relatives. Description [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
20240212 Aglaspis Spinifer
4 (four) is a number, numeral and digit. It is the natural number following 3 and preceding 5. It is a square number, the smallest semiprime and composite number, and is considered unlucky in many East Asian cultures. Evolution of the Hindu-Arabic digit Brahmic numerals represented 1, 2, and 3 with as many lines. 4 was simplified by joining its four lines into a cross that looks like the modern plus sign. The Shunga would add a horizontal line on top of the digit, and the Kshatrapa and Pallava evolved the digit to a point where the speed of writing was a secondary concern. The Arabs' 4 still had the early concept of the cross, but for the sake of efficiency, was made in one stroke by connecting the "western" end to the "northern" end; the "eastern" end was finished off with a curve. The Europeans dropped the finishing curve and gradually made the digit less cursive, ending up with a digit very close to the original Brahmin cross. While the shape of the character for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kodymirus Vagans
''Kodymirus'' is a genus of Early Cambrian arthropod, known from the Czech Republic. Although it possessed great appendage-like raptorial arms, it was not homologous with those of megacheirans. ''Kodymirus'' is currently considered a member of Vicissicaudata, closely related to aglaspidids, and more distantly to trilobites. It is part of a small and low-diversity Paseky Shale fauna group, which dwelt in brackish waters. Description ''Kodymirus'' was a small predator at long. Its distinctive feature is pair of large, serrated raptorial appendages. These appendages appear convergent to those of megacheirans and radiodonts, but are not homologous as they postantennular, suggesting raptorial arms evolved multiple times in Cambrian arthropods. Paleoecology ''Kodymirus'' inhabited the Paseky Shale, within the modern day Czech Republic, which may be a shallow marine environment or brackish estuary. Trace fossils from the Shale have been interpreted as ''Kodymirus'' raking ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
20200415 Cheloniellon Calmani
__NOTOC__ Year 415 ( CDXV) was a common year starting on Friday of the Julian calendar. At the time, it was known as the Year of the Consulship of Honorius and Theodosius (or, less frequently, year 1168 ''Ab urbe condita''). The denomination 415 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years. Events By place Roman Empire * Constantius, Roman general (''magister militum''), drives the Visigoths out of Gaul. He captures the usurper Priscus Attalus, and sends him under military escort to Ravenna. * The Visigoths invade the Iberian Peninsula and begin to conquer territory taken previously by the Vandals. King Athaulf and his pregnant wife Galla Placidia leave Gallia Narbonensis; they relocate at Barcelona. Their infant son, Theodosius, dies in infancy, eliminating an opportunity for a Roman-Visigothic line. Athaulf is assassinated in the palace while taking a bath. Sigeri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tardisia
''Tardisia'' is an extinct genus of vicissicaudatan arthropod known from the upper Carboniferous Mazon Creek fossil beds in northern Illinois. It is the youngest known member of the Artiopoda outside of the trilobites, at almost 100 million years younger than the next youngest in the Hunsrück Slate and Severnaya Zemlya Formation. Etymology ''Tardisia'' is named after the TARDIS from the TV show ''Doctor Who'', in reference to the large stratigraphic gap between it and the next youngest vicissicaudatans. The specific name ''broedeae'' honours Irene Broede, a Mazon Creek fossil collector. Description ''Tardisia'' lacks eyes, with a head shield (the frontal end is lost on the holotype, but according to descriptions and the paratype it was likely sub-semicircular) smaller than the first tergite. The trunk comprises seven tergites in the thorax, four with overlapping margins, and a postabdomen composed of the eighth segment, which lacks wide pleurae and instead bears a pair of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sidneyia Inexpectans
''Sidneyia'' is an extinct marine arthropod known from fossils found from the Early to the Mid Cambrian of China and the Mid Cambrian Burgess Shale of British Columbia, Canada. Description Sidneyia size comparison.svg, Size comparison of ''Sidneyia'' species Rsos211134f08 d.jpg, Biramous limb of ''Sidneyia inexpectans'' ''Sidneyia inexpectans'' reached lengths of at least . The largest known specimen of ''S. minor'' is around long and wide, while the largest specimen of ''S. malongensis'' is long and wide. The head shield is short, with notches present on the sides to accommodate stalked eyes, with the underside having a hypostome. The head has a pair of segmented antennae, as well as three pairs of post-antenal appendages. This was followed by a thorax, which had eight to ten segments/ tergites, each associated with a pair of biramous (two branched) appendages, this was followed with one to three abdomen segments/tergites, with the body terminating with a telson, which c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emeraldella Brutoni Reconstruction
''Emeraldella'' is a genus of arthropod known from the Middle Cambrian of North America. The type species ''E. brocki'' was described in 1912 from the Burgess Shale. 21 specimens of ''Emeraldella'' are known from the Greater Phyllopod bed, where they comprise < 0.1% of the community. A re-study on the species was done in 2012. A second species ''E. brutoni'' is known from the Wheeler Shale, which was described in 2011. An additional specimen of ''E. brutoni'' was described in 2019, which revealed more of the anatomy. It has been placed as a basal member of the clade Vicissicaudata within Artiopoda, a group of arthropods containing trilobites and their relatives. Description [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
