Pneumodesmus

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Pneumodesmus
Temporal range: Wenlock
Reconstruction of Pneumodesmus newmani
Scientific classification
Kingdom:
Phylum:
Subphylum:
Class:
Subclass:
Order:
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Genus:
Pneumodesmus
Species:
P. newmani
Binomial name
Pneumodesmus newmani
Wilson & Anderson, 2004 [1]
Photomicrograph of the type specimen

Pneumodesmus newmani is a species of millipede that lived during the late Wenlock epoch of the Silurian period around 428 million years ago.[1][2][3]

It is the first myriapod fossil, and the oldest known creature to have lived on land.[4] The single specimen was discovered in 2004 near Stonehaven, Aberdeenshire.[2]

Discovery and naming[change | change source]

The fossil of P. newmani was found by Mike Newman. He is a bus driver and amateur palaeontologist from Aberdeen. The fossil was in a layer of sandstone rocks on the foreshore of Cowie, near Stonehaven.[5] The species was later called "newmani" in honour of its finder. The fossil is kept in National Museum of Scotland, Edinburgh.[6]

Description[change | change source]

In the photograph above, you can see the back is covered with hard plates, and wispy slender legs. The animal is definitely segmented, and it is like, or related to, millipedes.[1]

Its cuticle has what look like openings or spiracles. These are part of a gas exchange system that would work in air. So P. newmani is thought to be the earliest documented arthropod with a tracheal system, and the first known oxygen-breathing animal on land.[4]

References[change | change source]

  1. 1.0 1.1 1.2 Heather M. Wilson & Lyall I. Anderson (2004). "Morphology and taxonomy of Paleozoic millipedes (Diplopoda: Chilognatha: Archipolypoda) from Scotland". Journal of Paleontology. 78 (1): 169–184. doi:10.1666/0022-3360(2004)078<0169:MATOPM>2.0.CO;2. S2CID 131201588.
  2. 2.0 2.1 "Fossil find 'oldest land animal'". BBC News. 2004.
  3. Wellman, C.H.; Lopes, G.; McKellar, Z.; Hartley, A. (2023). "Age of the basal 'Lower Old Red Sandstone' Stonehaven Group of Scotland: The oldest reported air-breathing land animal is Silurian (late Wenlock) in age". Journal of the Geological Society. The Geological Society of London. doi:10.1144/jgs2023-138. ISSN 0016-7649.
  4. 4.0 4.1 "Fossil millipede found to be oldest land creature". CNN (from Reuters). 2004.
  5. "Pneumodesmus newmani Exhibition". Stonehaven Guide. Archived from the original on 2016-12-24. Retrieved 2019-01-13.
  6. Selden, Paul & Read, Helen (2008). "The oldest land animals: Silurian millipedes from Scotland" (PDF). Bulletin of the British Myriapod & Isopod Group. 23: 36–37.{{cite journal}}: CS1 maint: multiple names: authors list (link)