Archimedes (bryozoan)

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Archimedes
Temporal range: Carboniferous–Permian
Fenestellidae - Archimedes species.JPG
Fossil stalks of Archimedes from Illinois, on display at Galerie de paléontologie et d'anatomie comparée in Paris
Scientific classification
Kingdom: Animalia
Phylum: Bryozoa
Class: Stenolaemata
Order: Fenestrida
Family: Fenestellidae
Genus: Archimedes[1]
Owen, 1838
Synonyms

Archimedipora d'Orbigny, 1849


Archimedes is a genus of Bryozoans belonging to the family Fenestellidae. The first use of the term "Archimedes" in relation to this genus was in 1838.[2]

Etymology[edit]

This genus of bryozoans is named Archimedes because of its corkscrew shape, in analogy to the Archimedes' screw, a type of water pump which inspired modern ship propellers. These forms are pretty common as fossils but they have been extinct since the Permian.

Species[edit]

  • Archimedes orientalis Schulga-Nesterenko 1936
  • Archimedes regina Crockford 1947
  • Archimedes stuckenbergi Nikiforova 1938

[3]

Fossil range[edit]

These bryozoans lived from the Carboniferous period (Tournaisian age) to the Permian period (Leonard age) (345.3 to 268.0 Ma), when this genus became extinct. [3][4]

Description[edit]

Right frame 
Arhimedes3d.jpg
Fossilized skeleton of Archimedes Bryozoan.

Archimedes were tubular-shaped zooids part of colonial animals. In life the individual animals formed spiral sheets that were attached to a central corkscrew skeletal structure. The whole structure would be attached to the seafloor or a shell. These bryozoans were stationary epifaunal suspension feeders. [3]

The live creature had a delicate calcareous lattice structure [5] representative of fenestrate growth forms, but in most fossils these latices have been destroyed, leaving only the spiral backbone.

Distribution[edit]

The majority of fossils of this genus are distributed throughout Europe and North America, but they have also been found in sediments of Afghanistan, Canada, Russia, and Australia. [3]

Notes[edit]

  1. ^ Col, Jeananda, 'Archimedes', Dinosaur and Paleontology Dictionary, 1996, accessed March 8, 2011
  2. ^ Duncan, Helen M. and W.H. Easton. "Archimedes and its Genotype." Journal of Paleontology. SEPM Society for Sedimentary Geology. Vol. 27, No. 5 (Sep., 1953), pp. 737–741.
  3. ^ a b c d The Paleobiology Database
  4. ^ Sepkoski, Jack Sepkoski's Online Genus Database - Bryozoa
  5. ^ Arduini, Paolo. Simon & Schuster's Guide to Fossils, 1986, p. 33