Mollisonia

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Mollisonia
Temporal range: Cambrian Stage 3–Floian
20190922 Mollisonia plenovenatrix.png
20191003 Mollisonia plenovenatrix side.png
Scientific classification
Kingdom:
Phylum:
Subphylum:
Order:
Mollisoniida
Genus:
Mollisonia

Walcott, 1912
Type species
Mollisonia symmetrica
Walcott 1912
Other species
  • Mollisonia plenovenatrixAria and Caron, 2019
  • Mollisonia gracilisWalcott, 1912
  • Mollisonia sinicaZhang et al., 2002
Synonyms

Houghtonites Raymond, 1931

Mollisonia in various views showing digestive and nervous systems 41467 2022 28054 Fig4 HTML.png
Mollisonia in various views showing digestive and nervous systems

Mollisonia is an extinct genus of Cambrian arthropod. Species are known from the Burgess Shale, Langston Formation, and Wheeler Shale of North America, as well as the Chengjiang Biota of China. [1] Twenty-one specimens of Mollisonia are known from the Greater Phyllopod bed, where they comprise less than 0.1% of the community. [2] Remains possibly attributable to the genus are also known from the Ordovician Fezouata Formation of Morocco and Bøggild Fjord Formation Greenland. [3] An observation published in 2019 suggests this genus is a basal chelicerate, closer to crown group Chelicerata than members of Habeliida. It is suggested to be closely related to Corcorania , Urokodia , and Thelxiope , which together form the clade Mollisoniida, which are thought to be closely related to Chelicerata. [4]

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<i>Molaria</i> Extinct genus of arthropods

Molaria is a genus of Cambrian arthropod, the type species M. spinifera is known from the Middle Cambrian Burgess Shale. 144 specimens of Molaria are known from the Greater Phyllopod bed, where they comprise 0.27% of the community. A second species M. steini was described from the Sirius Passet in Greenland in 2017.

Pirania is an extinct genus of sea sponge known from the Middle Cambrian Burgess Shale and the Ordovician Fezouata formation. It is named after Mount St. Piran, a mountain situated in the Bow River Valley in Banff National Park, Alberta. It was first described in 1920 by Charles Doolittle Walcott. 198 specimens of Pirania are known from the Greater Phyllopod bed, where they comprise 0.38% of the community.

Protospongia is a genus of Porifera known from the Middle Cambrian Burgess Shale. 102 specimens of Protospongia are known from the Greater Phyllopod bed, where they comprise 0.19% of the community.

<i>Balhuticaris</i> Extinct genus of arthropods

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.

References

  1. Zhang, Xingliang; Zhao, Yuanlong; Yang, Ruidong; Shu, Degan (November 2002). "The Burgess Shale arthropod Mollisonia (M. sinica new species): new occurrence from the Middle Cambrian Kaili fauna of southwest China". Journal of Paleontology. 76 (6): 1106–1108. doi:10.1017/S0022336000057917. ISSN   0022-3360. S2CID   130112985.
  2. Caron, Jean-Bernard; Jackson, Donald A. (October 2006). "Taphonomy of the Greater Phyllopod Bed community, Burgess Shale". PALAIOS. 21 (5): 451–65. doi:10.2110/palo.2003.P05-070R. JSTOR   20173022. S2CID   53646959.
  3. Peel, John S.; Willman, Sebastian; Pedersen, Stig A. Schack (March 2020). "Unusual preservation of an Ordovician (Floian) arthropod from Peary Land, North Greenland (Laurentia)". PalZ. 94 (1): 41–51. doi: 10.1007/s12542-019-00481-y . ISSN   0031-0220.
  4. Aria, Cédric; Caron, Jean-Bernard (September 2019). "A middle Cambrian arthropod with chelicerae and proto-book gills". Nature. 573 (7775): 586–589. doi:10.1038/s41586-019-1525-4. ISSN   0028-0836. PMID   31511691. S2CID   202550431.