Gelenoptron Temporal range: | |
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Artists interpretation of G. tentaculatum | |
Scientific classification | |
Kingdom: | Animalia |
Phylum: | Cnidaria |
Class: | Hydrozoa (?) |
Genus: | † Gelenoptron |
Species: | †G. tentaculatum |
Binomial name | |
†Gelenoptron tentaculatum Conway Morris 1993 [1] | |
Gelenoptron tentaculatum is an extinct, cnidarian-like organism represented by a single specimen and counterslab from the Burgess Shale. The holotype of G. tentaculatum was originally identified as a second specimen of the Animalia incertae sedis , Redoubtia , but established as a separate genus by Simon Conway Morris in 1993. A reflective shield recalls the float of chondrophore hydrozoans. [1]
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.
Hallucigenia is a genus of Cambrian animal resembling worms, known from articulated fossils in Burgess Shale-type deposits in Canada and China, and from isolated spines around the world. The generic name reflects the type species' unusual appearance and eccentric history of study; when it was erected as a genus, H. sparsa was reconstructed as an enigmatic animal upside down and back to front. Hallucigenia is later recognized as part of lobopodians, a grade of Paleozoic panarthropods where the velvet worms, water bears, and arthropods arose.
Pikaia gracilens is an extinct, primitive chordate animal known from the Middle Cambrian Burgess Shale of British Columbia. Sixteen specimens are known from the Greater Phyllopod bed, where they comprised 0.03% of the community. It resembled the lancelet and perhaps swam much like an eel.
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 cm (2 inch) when fully grown, although a range of juvenile specimens are known, the smallest being 2 millimetres (0.079 in) long.
Ottoia is a stem-group archaeopriapulid worm known from Cambrian fossils. Although priapulid-like worms from various Cambrian deposits are often referred to Ottoia on spurious grounds, the only clear Ottoia macrofossils come from the Burgess Shale of British Columbia, which was deposited 508 million years ago. Microfossils extend the record of Ottoia throughout the Western Canada Sedimentary Basin, from the mid- to late- Cambrian. A few fossil finds are also known from China.
Peytoia is a genus of hurdiid radiodont that lived in the Cambrian period, containing two species, Peytoia nathorsti and Peytoia infercambriensis. Its two frontal appendages had long bristle-like spines, it had no fan tail, and its short stalked eyes were behind its large head.
Orthrozanclus is a genus of sea creatures from the Middle Cambrian Burgess shale. Animals in this genus were one to two centimeters long, with spikes protruding from their armored bodies. The placement of this genus into a specific family is not universally accepted.
Burgessia is an extinct genus of arthropod from the Middle Cambrian. Its fossils have been found in the Burgess Shale in British Columbia, Canada. Many of its fossils have been found. 1383 specimens of Burgessia are known from the Greater Phyllopod bed, where they comprise 2.63% of the community.
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. Specimens have also been found at Marble Canyon. The genus was described by Conway Morris (1979) and re-examined by Eibye-Jacobsen (2004).
Capsospongia, formerly known as Corralia or Corralio, is a middle Cambrian sponge genus known from 3 specimens in the Burgess shale. Its type and only species is Capsospongia undulata. It has a narrow base, and consists of bulging rings which get wider further up the sponge, resulting in a conical shape. Its open top was presumably used to expel water that had passed through the sponge cells and been filtered for nutrients.
The fossils of the Burgess Shale, like the Burgess Shale itself, 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 book Wonderful Life describes the history of discovery up to the early 1980s, although his analysis of the implications for evolution has been contested.
Mackenzia is an elongated bag-like animal known from the Middle Cambrian Burgess Shale. It attached directly to hard surfaces, such as brachiopod shells. 14 specimens of Mackenzia are known from the Greater Phyllopod bed, where they comprise <0.1% of the community. Mackenzia was originally described by Charles Walcott in 1911 as a holothurian echinoderm. Later, Mackenzia is thought to be a cnidarian and appears most similar to modern sea anemones.
Louisella is a genus of worm known from the Middle Cambrian Burgess Shale. It was originally described by Charles Walcott in 1911 as a holothurian echinoderm, and represents a senior synonym of Miskoia, which was originally described as an annelid. 48 specimens of Louisella are known from the Greater Phyllopod bed, where they comprise < 0.1% of the community. It has been stated to have palaeoscolecid-like sclerites, though this is not in fact the case.
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).
Oesia disjuncta is a monospecific genus known from the Middle Cambrian Burgess Shale. 1147 specimens of Oesia are known from the Greater Phyllopod bed, where they comprise 2.18% of the community. Despite some similarities to the chaetognaths, its affinity is unknown, though recent data suggest it may be affiliated with hemichordates.
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).
Lecythioscopa is a genus of probable archaeopriapulid known from two specimens from the Walcott Quarry from the Middle Cambrian Burgess Shale.
Peytoia nathorsti is a species of hurdiid radiodont from the Burgess Shale. It is the type species of the genus Peytoia.