Pneumodesmus

genus of Silurian millipedes

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]

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

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

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

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

  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)