Arandaspis prionotolepis is an extinct species of jawless fish that lived in the Ordovician period, about 480 to 470 million years ago. Its remains were found in the Stairway Sandstone near Alice Springs, Australia in 1959, but it was not determined that they were the oldest known vertebrates until the late 1960s. Arandaspis is named after a local Indigenous Australian people, the Aranda (now currently called Arrernte).

Arandaspis
Temporal range: Early Ordovician
480–470 Ma
Fossil of Arandaspis prionotolepis from Natural History Museum in London
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Infraphylum: Agnatha
Class: Pteraspidomorphi
Order: Arandaspidiformes
Family: Arandaspididae
Genus: Arandaspis
Ritchie & Gilbert-Tomlinson, 1977
Type species
Arandaspis prionotolepis
Ritchie & Gilbert-Tomlinson, 1977
Species[1]
  • A. prionotolepis Ritchie & Gilbert-Tomlinson, 1977
  • A. sp. Young, 1997

Description

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Life restoration, with trunk morphology based on speculation in Ritchie and Gilbert-Tomlinson (1977) and tail based on Sacabambaspis

Arandaspis is estimated to reach around 12–14 cm (5–6 in) long, with a body covered in rows of knobbly armoured scutes. The front of the body and the head were protected by hard plates with openings for the eyes, nostrils and gills. It probably was a filter-feeder. Morphology of trunk and tail is unknown.[2] According to comparison with other early ostracoderms, it would lacked paired fins and caudal fin would be simple shape,[2] although another arandaspid Sacabambaspis had the tail that consist dorsal and ventral webs and an elongated notochordal lobe.[3]

See also

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References

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  1. ^ "Pteraspidomorphi". Retrieved 28 October 2013.
  2. ^ a b Ritchie, Alexander; Gilbert-Tomlinson, Joyce (1977). "First Ordovician vertebrates from the Southern Hemisphere". Alcheringa: An Australasian Journal of Palaeontology. 1 (4): 351–368. doi:10.1080/03115517708527770. ISSN 0311-5518.
  3. ^ Pradel, Alan; Sansom, Ivan. J; Gagnier, Pierre-Yves; Cespedes, Ricardo; Janvier, Philippe (2006-11-14). "The tail of the Ordovician fish Sacabambaspis". Biology Letters. 3 (1): 73–76. doi:10.1098/rsbl.2006.0557. ISSN 1744-9561. PMC 2373808.
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