Burgessochaeta Temporal range: | |
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Reconstruction of Burgessochaeta setigera | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Annelida |
Class: | Polychaeta |
Family: | † Burgessochaetidae Conway Morris, 1979 |
Genus: | † Burgessochaeta Conway Morris, 1979 |
Species: | †B. setigera |
Binomial name | |
†Burgessochaeta setigera (Walcott, 1911) | |
Synonyms | |
Canadia setigeraWalcott, 1911 |
Burgessochaeta is an extinct genus of polychaete annelids from the Middle Cambrian. Its fossils have been found in the Burgess Shale in British Columbia, Canada. A total of 189 specimens of Burgessochaeta are known from the Greater Phyllopod bed, where they comprise 0.36% of the community. [1] Specimens have also been found at Marble Canyon. [2] The genus was described by Conway Morris (1979) [3] and re-examined by Eibye-Jacobsen (2004). [4]
Burgessochaeta had two long tentacles on its head. The rest of the body had between 16 and 30 segments (possibly indicating multiple species). Each segment had two groups of long chaetae on it, which Burgessochaeta presumably used to swim. Burgessochaeta is not thought to have had eyes. The body grew slightly wider towards the posterior end of the animal. [5]
Burgessochaeta is thought to have been a decomposer or scavenger on organic material. It probably swam, as its bristles were much too long to be useful for moving itself in a burrow. Specimens have been found from both continental slope and deep-water environments, indicating that this was a widespread animal. [6]
The Burgess Shale is a fossil-bearing deposit exposed in the Canadian Rockies of British Columbia, Canada. It is famous for the exceptional preservation of the soft parts of its fossils. At 508 million years old, it is one of the earliest fossil beds containing soft-part imprints.
Aysheaia is an extinct genus of soft-bodied lobopodian, known from the Middle Cambrian Burgess Shale of British Columbia, Canada
Wiwaxia is a genus of soft-bodied animals that were covered in carbonaceous scales and spines that protected it from predators. Wiwaxia fossils—mainly isolated scales, but sometimes complete, articulated fossils—are known from early Cambrian and middle Cambrian fossil deposits across the globe. The living animal would have measured up to 5 centimetres (2 in) when fully grown, although a range of juvenile specimens are known, the smallest being 2 millimetres (0.08 in) long.
Yohoia is an extinct genus of megacheiran arthropod from the Cambrian period that has been found as fossils in the Burgess Shale formation of British Columbia, Canada. The type species, Yohoia tenuis, was described in 1912 by Walcott, who considered it an anostracan crustacean. 711 specimens of Yohoia are known from the Greater Phyllopod bed, where they comprise 1.35% of the community. In 2015, Conway Morris et al. reported another species, Y. utahana, from the Marjum Formation, Utah.
Odontogriphus is a genus of soft-bodied animals known from middle Cambrian Lagerstätte. Reaching as much as 12.5 centimetres (4.9 in) in length, Odontogriphus is a flat, oval bilaterian which apparently had a single muscular foot and a "shell" on its back that was moderately rigid but of a material unsuited to fossilization.
Dinomischusis an extinct genus of stalked filter-feeding animals within the Cambrian period, with specimens known from the Burgess Shale and the Maotianshan Shales. While long of uncertain affinities, recent studies have suggested it to be a stem-group ctenophore.
Halwaxiida or halwaxiids is a proposed clade equivalent to the older orders Sachitida He 1980 and Thambetolepidea Jell 1981, loosely uniting scale-bearing Cambrian animals, which may lie in the stem group to molluscs or lophotrochozoa. Some palaeontologists question the validity of the Halwaxiida clade.
Odaraia is a genus of bivalved arthropod from the Middle Cambrian. Its fossils, which reach 15 centimetres (5.9 in) in length, have been found in the Burgess Shale in British Columbia, Canada.
Canadia is a genus of extinct annelid worm present in Burgess Shale type Konservat-Lagerstätte. It is found in strata dating back to the Delamaran stage of the Middle Cambrian around 505 million years ago, during the time of the Cambrian explosion. It was about 3 centimeters in length. Charles Doolittle Walcott named Canadia in 1911 after Canada, the country from which its remains have been found. 28 specimens of Canadia are known from the Greater Phyllopod bed, where they comprise 0.05% of the community.
The fossils of the Burgess Shale, like the Burgess Shale itself, are fossils that formed around 505 million years ago in the mid-Cambrian period. They were discovered in Canada in 1886, and Charles Doolittle Walcott collected over 65,000 specimens in a series of field trips up to the alpine site from 1909 to 1924. After a period of neglect from the 1930s to the early 1960s, new excavations and re-examinations of Walcott's collection continue to reveal new species, and statistical analysis suggests that additional discoveries will continue for the foreseeable future. Stephen Jay Gould's 1989 book Wonderful Life describes the history of discovery up to the early 1980s, although his analysis of the implications for evolution has been contested.
Eldonia is an extinct soft-bodied cambroernid animal of unknown affinity, best known from the Fossil Ridge outcrops of the Burgess Shale, particularly in the 'Great Eldonia layer' in the Walcott Quarry. In addition to the 550 collected by Walcott, 224 specimens of Eldonia are known from the Greater Phyllopod bed, where they comprise 0.43% of the community. Species also occur in the Chengjiang biota, Siberia, and in Upper Ordovician strata of Morocco.
Herpetogaster is an extinct cambroernid genus of animal from the Early Cambrian Chengjiang biota of China, Blang Formation of China, Pioche Formation of Nevada and Middle Cambrian Burgess Shale of Canada containing the species Herpetogaster collinsi and Herpetogaster haiyanensis.
The Phyllopod bed, designated by USNM locality number 35k, is the most famous fossil-bearing member of the Burgess Shale fossil Lagerstätte. It was quarried by Charles Walcott from 1911–1917, and was the source of 95% of the fossils he collected during this time; tens of thousands of soft-bodied fossils representing over 150 genera have been recovered from the Phyllopod bed alone.
Cambrorhytium is an enigmatic fossil genus known from the Latham Shale (California), and the Chengjiang (China) and Burgess Shale lagerstätte. 350 specimens of Cambrorhytium are known from the Greater Phyllopod bed, where they comprise 0.7% of the community.
Insolicorypha is a genus of polychaetes known from the Middle Cambrian Burgess Shale. A single specimen of Insolicorypha is known from the Greater Phyllopod bed. The genus was described by Conway Morris (1979) and re-examined by Eibye-Jacobsen (2004).
Peronochaeta is a genus of annelid known from the Middle Cambrian Burgess Shale. 19 specimens of Peronochaeta are known from the Greater Phyllopod bed, where they comprise < 0.1% of the community. The genus was described by Conway Morris (1979) and re-examined by Eibye-Jacobsen (2004).
Pollingeria is a problematic genus of animals of the Middle Cambrian Burgess Shale. 3080 specimens of Pollingeria are known from the Greater Phyllopod bed, where they comprise 5.85% of the community.
Stephenoscolex is a genus of polychaete worm known from the Middle Cambrian Burgess Shale. 150 specimens of Stephenoscolex are known from the Greater Phyllopod bed, where they comprise 0.29% of the community. The genus was described by Conway Morris (1979) and re-examined by Eibye-Jacobsen (2004).
Phragmochaeta canicularis is an extinct animal belonging to the annelids and lived in the Early Cambrian. Fossils have only been found in the Buen Formation at the Sirius Passet Lagerstätte, Greenland and the animal is probably the first polychaete.
Balhuticaris is a genus of extinct bivalved hymenocarine arthropod that lived in the Cambrian aged Burgess Shale in what is now British Columbia around 506 million years ago. This extremely multisegmented arthropod is the largest member of the group, and it was even one of the largest animals of the Cambrian, with individuals reaching lengths of 245 mm (9 in). Fossils of this animal suggests that gigantism occurred in more groups of Arthropoda than had been previously thought. It also presents the possibility that bivalved arthropods were very diverse, and filled in a lot of ecological niches.