Dicksonosteus
Dicksonosteus is an extinct genus of basal arthrodire placoderm fish which lived during the Early Devonian period of Spitsbergen, Norway.[1]
| Dicksonosteus Temporal range: | |
|---|---|
 | |
| D. arcticus fossil | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | †Placodermi |
| Order: | †Arthrodira |
| Clade: | †Phlyctaenioidei |
| Family: | †Phlyctaeniidae |
| Genus: | †Dicksonosteus Goujet, 1975 |
| Type species | |
| †Dicksonosteus arcticus Goujet, 1975 | |
Classification
Within Arthrodira, Dicksonosteus is considered a member of "Phylctaenii", a paraphyletic grouping within the clade Phlyctaenioidei, basal to the suborder Brachythoraci.[1][2] Dicksonosteus was once considered an actinolepid, but is now grouped within the family Phlyctaeniidae.[3] Dicksonosteus is most closely related to Arctolepis and Heintzosteus.[2]
Description
Dicksonosteus is considered basal to the arthrodires, the most successful and widespread group of placoderms during the Devonian period notable for the movable joint between the armour sections surrounding their heads and bodies. Its body is wide and flat, and unlike the more robust-jawed arthrodires that would come after it, such as Dunkleosteus and Coccosteus, its jaws were relatively feeble, suggesting the lifestyle of a benthic fish that subsisted primarily on smaller, softer-bodied animals. Exceptionally preserved fossil specimens of Dicksonosteus from Spitsbergen, Norway display details of its braincase and internal anatomy, the details of which have been described.How?
References
- Zhu, You-An; Zhu, Min; Wang, Jun-Qing (1 April 2016). "Redescription of Yinostius major (Arthrodira: Heterostiidae) from the Lower Devonian of China, and the interrelationships of Brachythoraci". Zoological Journal of the Linnean Society. 176 (4): 806–834. doi:10.1111/zoj.12356. ISSN 0024-4082.
- Dupret, V.; Zhu, M. I. N.; Wang, J. N. Q. (2009). "The morphology of Yujiangolepis liujingensis (Placodermi, Arthrodira) from the Pragian of Guangxi (south China) and its phylogenetic significance". Zoological Journal of the Linnean Society. 157: 70. doi:10.1111/j.1096-3642.2009.00519.x.
- Goujet, D. (1975). Dicksonosteus, un nouvel arthrodire du Dévonien du Spitsberg—Remarques sur le squelette viscéral des Dolichothoraci. Colloques internationaux du Centre National de la Recherche Scientifique, 218, 81-99.
