Spriggina
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 Fossil of S. floundensi
 Sketch reconstruction
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Spriggina was an animal of the Ediacaran period, fossils of which have been found in the Ediacara Hills of Australia. The organisms grew to around three centimeters in length. The shape of Spriggina is roughly oblong, and segmented looking. The segments are sometimes curved with the appearance of head end and tail end. The segments are attached to a central axis. Some fossils have what may be a circular mouth at the centre of the semicircular head, although the small size of the creature and large grains of the containing sandstones make fossils difficult to interpret in this area. It appears to be legless. The body is stiff, always making a mould in the lower surface of the fossil bed.
Some researchers have claimed that the symmetry is not exactly bilaterean but is a glide reflection, where the opposite segment is shifted by half an interval.[1][2][3] In some specimens the body segments tilt backwards, making roughly chevron patterns; while in others they are more or less straight. There also appear to be fairly complex variations between these two.
Spriggina has been classified as a vendobiont, an annelid and an arthropod. It resembles a trilobite, and may be an ancestor of them. Spriggina could have been the predator that initiated the Cambrian transition.[4]
Named species are
- Spriggina floundersi named by Martin Glaessner in 1958
- Spriggina ovata named by Glaessner & Mary Wade in 1966
The genus was named after Reg Sprigg who discovered the Precambrian fossils in Ediacara Hills, and was a proponent of their recognition as multicellular organisms.
[edit] References
- ^ Ediacara Assemblage
- ^ University of Califormis Museaum of Paleontology - Vendian Animals: Spriggina
- ^ Spriggina at Tripod.com
- ^ Spriggina is a Trilobitoid Ecdysozoan
- Glaessner, Martin F. 1958: New Fossils from the Base of the Cambrian in South Australia. Transactions of the Royal Society of South Australia 81: 185-188.
- Glaessner, Martin F.; Wade, Mary 1966: The Late Precambrian Fossils from Ediacara, South Australia. Palaeontology 9 (4), pp. 599-628.
