Maiocercus

Maiocercus
Temporal range: 310 Ma
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Fossil of Maiocercus celticus located in Musee d'Histoire Naturelle, Brussels, Belgium.
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Chelicerata
Class: Arachnida
Order: †Trigonotarbida
Family: †Anthracomartidae
Genus: †Maiocercus
Pocock, 1902
Species:
†M. celticus
Binomial name
†Maiocercus celticus
(Pocock, 1902)
Synonyms
  • Brachypyge celtica Pocock, 1902
  • Maiocercus orbicularis Gill, 1911

Maiocercus celticus is a species of early trigonotarbid arachnid from the Upper Carboniferous of Westhoughton, Lancashire, UK. The species was first described in 1902, with a "new species" being described in 1911 (M. orbicularis) which has been proven as being a junior synonym of M. celticus.[1][2]

M. celticus is the type species of the genus Maiocercus.[3]

Artist's reconstruction of M. celticus, showing 5 rows of dorsal plates

Originally zoologist Reginald Innes Pocock compared M. celticus to Brachypyge, with later evidence showing that Brachypyge had "opisthosoma which were much longer than wide; with the pleural laminæ of the second and third pleura-bearing terga being inclined slightly backwards" (Brachypyge) with Maiocercus having the “opisthosoma much wider than long; the pleural laminæ of the first, second, third, and fourth sterna being inclined slightly forwards”.[4]

The original drawing which showed Maiocercus described a pitting on the underside of the slightly forwarded laminæ, with a non-uniform concavity on the outer margins of them. The concavity is most well-marked in the fifth, sixth, seventh and eighth somites, with the opposite happening on the second, third and fourth somites.[5]

  1. ^ Dunlop, Jason A.; Horrocks, Carl A. (1996). "A new specimen of the Carboniferous trigonotarbid arachnid Maiocercus celticus (Pocock 1902) from Lancashire, UK". Proceedings of the Yorkshire Geological Society. 51: 23–31. doi:10.1144/pygs.51.1.23.
  2. ^ Craven, D. J.; Dunlop, J. A. (2008). "The holotype of the trigonotarbid arachnid Maiocercus orbicularis Gill, 1911, a junior synonym of M. Celticus (Pocock, 1902)". Proceedings of the Yorkshire Geological Society. 57: 61–62. doi:10.1144/pygs.57.1.61.
  3. ^ Yorkshire Geological Society. Yorkshire Geological Society. 17 September 2009. Retrieved 12 August 2022 – via Google Books.
  4. ^ Gill, E. Leonard (1911). "II.—A Carboniferous Arachnid from Lancashire". Geological Magazine. 8 (9): 395–398. Bibcode:1911GeoM....8..395G. doi:10.1017/S0016756800116383. S2CID 129301901.
  5. ^ Geological Magazine. Cambridge University Press. 10 July 2015. Retrieved 12 August 2022 – via Google Books.