Liwia Plana

	Liwia Plana ''Liwia'' is a genus of nektaspid, a soft-bodied stem-group chelicerate. It includes the following species, both are known from borehole samples several kilometers in depth from the Zawiszyn Formation in Poland, which has also yielded ''Peytoia infercambriensis ''Peytoia infercambriensis'' is a species of hurdiid radiodont in the genus ''Peytoia''. ''P. infercambriensis'' is the geologically oldest known radiodont; its remains date to the third age of the Cambrian. The type and only known specimen, ....'' ''Liwia plana'' Lendzion, 1975 ''Liwia convexa'' Lendzion 1975 References Nektaspida Fossils of Poland {{nektaspida-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	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]
picture info	Chelicerata The subphylum Chelicerata (from New Latin, , ) constitutes one of the major subdivisions of the phylum Arthropoda. It contains the sea spiders, horseshoe crabs, and arachnids (including Opiliones, harvestmen, scorpions, spiders, Solifugae, solifuges, Parasitiformes, ticks, and Acariformes, mites, among many others), as well as a number of extinct lineages, such as the eurypterids (sea scorpions) and chasmataspidids. The Chelicerata originated as marine animals in the Middle Cambrian period; the first confirmed chelicerate fossils, belonging to ''Sanctacaris'', date from Burgess Shale, 508 million years ago. The surviving marine species include the four species of xiphosurans (horseshoe crabs), and possibly the 1,300 species of Pycnogonida, pycnogonids (sea spiders), if the latter are indeed chelicerates. On the other hand, there are over 77,000 well-identified species of air-breathing chelicerates, and there may be about 500,000 unidentified species. Like all arth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Zawiszyn Formation Zawiszyn may refer to the following places: * Zawiszyn, Kuyavian-Pomeranian Voivodeship (north-central Poland) * Zawiszyn, Masovian Voivodeship (east-central Poland) * Zawiszyn, Warmian-Masurian Voivodeship (north Poland) {{geodis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Peytoia Infercambriensis ''Peytoia infercambriensis'' is a species of hurdiid radiodont in the genus ''Peytoia''. ''P. infercambriensis'' is the geologically oldest known radiodont; its remains date to the third age of the Cambrian. The type and only known specimen, a partial appendage, was found in a core sample from a borehole nearly five kilometers deep in northern Poland. ''P. infercambriensis'' was previously regarded as belonging to a separate genus, ''Cassubia'', named after the historical region of Kashubia in which the specimen was found, but ''Cassubia'' is now considered a junior synonym of ''Peytoia''. History of study Discovery and naming The holotype—and only—specimen was recovered from the Kościerzyna borehole, in the Cambrian Stage 3 aged Zawiszyn Formation. It was found in the Fallotaspis Zone making it older than the Chengjiang biota. It was described by Kazimiera Lendzion in 1975 and given the name ''Pomerania infercambriensis'', in reference to its Lower Cambrian provenance a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]