Microcleidus

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Microcleidus
Temporal range: Toarcian
~182–175  Ma
Microcleidus NHM.jpg
Fossil M. homalospondylus
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Superorder: Sauropterygia
Order: Plesiosauria
Family: Microcleididae
Genus: Microcleidus
Watson, 1909
Type species
Plesiosaurus homalospondylus
(Owen, 1865)
Other species
  • M. macropterus(Seeley, 1865)
  • M. tournemirensis(Sciau et al., 1990)
  • M. melusinaeVincent et al., 2019
Synonyms

M. macropteus

  • Plesiosaurus macropteusSeeley, 1865
  • Eretmosaurus macropterusBenton and Spencer, 1995

M. tournemirensis

  • Plesiosaurus tournemirensisSciau et al., 1990
  • Occitanosaurus tournemirensis
    Bardet et al., 1999

Microcleidus is an extinct genus of sauropterygian reptile belonging to the Plesiosauroidea. The species has 40 neck vertebrae and a short tail of 28 vertebrae. Fossils of the genus have been found in France, the Posidonia Shale in Germany and Luxembourg, and the Alum Shale Formation of England.

Contents

Description

Restoration of M. homalospondylus Microcleidus homalospondylus.png
Restoration of M. homalospondylus
Fossils of M. tournemirensis alongside belemnites Espalion - Musee Joseph Vaylet (13).jpg
Fossils of M. tournemirensis alongside belemnites

The type species, M. homalospondylus, was the largest, measuring 5.1 m (17 ft) long and weighing 650 kg (1,430 lb). Other species were smaller: M. tournemirensis was about 4 m (13 ft) long and weighed 300 kg (660 lb), and M. melusinae was about 3 m (9.8 ft) long and weighed 120 kg (260 lb). [1] [2] [3]

Classification

Species include: Microcleidus homalospondylus (Owen 1865) and Microcleidus macropterus (Seeley 1865).

Occitanosaurus tournemirensis (originally "Plesiosaurus" tournemirensis), was named by Sciau et al. in 1990, based on a nearly complete skeleton of an animal approximately 4 meters (13 ft) long. [1] It was later found to be a species of Microcleidus.

Fossils and reconstruction of Microcleidus tournemirensis Espalion - Musee Joseph Vaylet (12).jpg
Fossils and reconstruction of Microcleidus tournemirensis

The following cladogram follows an analysis by Ketchum & Benson, 2011. [4]

  Pistosauria  

See also

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References

  1. 1 2 Ketchum HF, Benson RBJ. Global interrelationships of Plesiosaur (Reptilia, Sauropterygia) and the pivotal role of taxon sampling in determining the outcome of phylogenetic analyses. Biological Reviews
  2. Valentin Fischer; Nikolay G. Zverkov; Maxim S. Arkhangelsky; Ilya M. Stenshin; Ivan V. Blagovetshensky; Gleb N. Uspensky (2020). "A new elasmosaurid plesiosaurian from the Early Cretaceous of Russia marks an early attempt at neck elongation". Zoological Journal of the Linnean Society. 192 (4): 1167–1194. doi:10.1093/zoolinnean/zlaa103. hdl:2268/251614. Supplementary Information
  3. Paul, Gregory S. (2022). The Princeton Field Guide to Mesozoic Sea Reptiles. Princeton University Press. pp. 108–109. doi:10.1515/9780691241456. ISBN   9780691193809. S2CID   251553177.
  4. Hilary F. Ketchum; Roger B. J. Benson (2011). "A new pliosaurid (Sauropterygia, Plesiosauria) from the Oxford Clay Formation (Middle Jurassic, Callovian) of England: evidence for a gracile, longirostrine grade of Early-Middle Jurassic pliosaurids". Special Papers in Palaeontology. 86: 109–129.

Bibliography