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The Cambrian chordates are an extinct group of animals belonging to the phylum Chordata that lived during the Cambrian, between 538 and 485 million years ago.The first Cambrian chordate known is Pikaia gracilens, a lancelet-like animal from the Burgess Shale in British Columbia, Canada.
Pikaia gracilens is an extinct, primitive chordate marine animal known from the Middle Cambrian Burgess Shale of British Columbia.Described in 1911 by Charles Doolittle Walcott as an annelid, and in 1979 by Harry B. Whittington and Simon Conway Morris as a chordate, it became "the most famous early chordate fossil", [1] or "famously known as the earliest described Cambrian chordate". [2]
Chordata is the third-largest phylum of the animal kingdom (behind only the protostomal phyla Arthropoda and Mollusca) and is also one of the most ancient animal taxons. Chordate fossils have been found from as early as the Cambrian explosion over 539 million years ago. [11]
It was interpreted by paleontologist C. D. Walcott in 1911 as a polychaete worm.Although some paleontologists regarded it as an early chordate allied with Pikaia et al., Conway Morris suggested in 1993 that it might be a Cambrian descendant of the Vendian form Pteridinium, and a frondose morphology was accepted, [4] until a 2024 study found Emmonsaspis to be in a polytomy with Metaspriggina ...
An important part of recognizing the structure as a nerve cord was fossilized nervous systems in other animals from the Cambrian Period (541 million to 485.4 million years ago) that were ...
3D restoration. Haikouichthys is about 2.5 cm (1 in) long and is narrower than Myllokunmingia, another putative chordate that comes from the same beds. [2] The holotype of Haikouichthys ercaicunensis was found in the Yuanshan member of the Qiongzhusi Formation in the 'Eoredlichia' Zone near Ercai Village in the Haikou Subdistrict (not to be confused with the city of Haikou in Hainan) of Xishan ...
Metaspriggina is a genus of chordate initially known from two specimens in the Middle Cambrian Burgess Shale [4] and 44 specimens found in 2012 at the Marble Canyon bed in Kootenay National Park. [1] Life reconstruction of Metaspriggina walcotti Reconstruction of Metaspriggina based on the Burgess Shale specimens available in 2009.
Myllokunmingia is a genus of basal chordate from the Lower Cambrian Maotianshan shales of China 518 mya and is thought to be a vertebrate, [2] although this is not conclusively proven. [3] The type species M. fengjiaoa is 28 mm long and 6 mm high. It is among the oldest possible craniates, found in the lower Cambrian Chengjiang).