Leanchoilia

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Leanchoilia
Temporal range: Cambrian Stage 3–Middle Cambrian
Leanchoilia superlata study 2.jpg
Leanchoilia superlata
Leanchoilia superlata study.jpg
Reconstruction of Leanchoilia superlata
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Class: Megacheira
Order: Leanchoilida
Størmer, 1944
Family: Leanchoiliidae
Raymond, 1935
Genus: Leanchoilia
Walcott, 1912
Type species
Leanchoilia superlata
Walcott, 1912
Other species
  • Leanchoilia illecebrosa(Hou, 1987)
  • Leanchoilia obesaHe et al., 2017
  • Leanchoilia persephoneSimonetta, 1970
  • Leanchoilia protogoniaSimonetta, 1970
  • Leanchoilia robisoniBabcock et al., 2012
  • Leanchoilia? hanceyiBriggs et al., 2008

(but see text)

Synonyms
Synonyms of Leanchoilia
  • BidentiaWalcott, 1912
Synonyms of L. superlata
  • Bidentia difficilisWalcott, 1912
Synonyms of L. illecebrosa

Leanchoilia is a megacheiran arthropod known from Cambrian deposits of the Burgess Shale in Canada and the Chengjiang biota of China. [1]

Contents

Description

Restoration of Leanchoilia superlata 20191027 Leanchoilia superlata.png
Restoration of Leanchoilia superlata

L. superlata was about 5 centimetres (2.0 in) long and had long, whip-like flagellae extending from its great appendages. Its internal organs are occasionally preserved within the substrate in three dimensions. [2] [3] Their two pairs of eyes are protected and covered by their exterior head shields, with two eyes being located on each side. [4] [5]

Species

Seven species are tentatively accepted today: L. superlata (the type species), L. persephone and L. protogonia from the Burgess Shale, L. illecebrosa and L. obesa from the Chengjiang biota, ''L. robisoni from Kaili, and L.? hanceyi from the Spence Shale. L. superlata and L. persephone may however be examples of sexual dimorphism. [6] [7] [8]

Distribution

55 specimens of Leanchoilia are known from the Greater Phyllopod bed, where they comprise 0.1% of the community. [9]

See also

Related Research Articles

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References

  1. "Burgess Shale: Leanchoilia superlata (an arthropod)". Smithsonian Institution National Museum of Natural History . Retrieved 6 July 2017.
  2. Nicholas J. Butterfield (2002). "Leanchoilia guts and the interpretation of three-dimensional structures in Burgess Shale-type fossils". Paleobiology . 28 (1): 155–171. doi:10.1666/0094-8373(2002)028<0155:LGATIO>2.0.CO;2. S2CID   85606166.
  3. Brigitte Schoenemann & Euan N. K. Clarkson (2012). "The eyes of Leanchoilia". Lethaia . 45 (4): 524–531. doi:10.1111/j.1502-3931.2012.00313.x.
  4. Schoenemann, B., & Clarkson, E. N. K. (2012). The eyes of Leanchoilia. Lethaia, 45(4), 524–531.
  5. García-Bellido, D. C., & Collins, D. (2007). Reassessment of the Genus Leanchoilia(Arthropoda, Arachnomorpha) from the Middle Cambrian Burgess Shale, British Columbia, Canada. Palaeontology, 50(3), 693–709.
  6. Diego C. García-Bellido & Desmond Collins (2007). "Reassessment of the genus Leanchoilia (Arthropoda, Arachnomorpha) from the Middle Cambrian Burgess Shale, British Columbia, Canada". Palaeontology . 50 (3): 693–709. Bibcode:2007Palgy..50..693G. doi: 10.1111/j.1475-4983.2007.00649.x .
  7. Liu, Yu; Hou, Xian-Guang; Bergström, J. (2007). "Chengjiang arthropod Leanchoilia illecebrosa (Hou, 1987) reconsidered". GFF . 129 (3): 263–272. doi:10.1080/11035890701293263. S2CID   84150456.
  8. He, Yu-Yang; Cong, Pei-Yun; Liu, Yu; Edgecombe, Gregory D.; Hou, Xian-Guang (2017). "Telson morphology of Leanchoiliidae (Arthropoda: Megacheira) highlighted by a new Leanchoilia from the Cambrian Chengjiang biota". Alcheringa: An Australasian Journal of Palaeontology . 41 (4): 581–589. doi:10.1080/03115518.2017.1320425. S2CID   90593555.
  9. Caron, Jean-Bernard; Jackson, Donald A. (October 2006). "Taphonomy of the Greater Phyllopod Bed community, Burgess Shale". PALAIOS. 21 (5): 451–65. Bibcode:2006Palai..21..451C. doi:10.2110/palo.2003.P05-070R. JSTOR   20173022. S2CID   53646959.