Namapoikia

Namapoikia rietoogensis is among the earliest known animals to produce a calcareous (probably aragonite[1]) skeleton.[2] Known from the Ediacaran period, before the Cambrian explosion of calcifying animals, the long-lived organism grew up to a metre in diameter and resembles a colonial sponge.[3][4] It was an encruster, filling vertical fissures in the reefs in which it originally grew.[5]

Namapoikia
Temporal range: 549 Ma
↓
(Terminal Ediacaran)
Scientific classification
Kingdom: Animalia
Phylum: Porifera (?)
Genus: †Namapoikia
Wood et al. 2002
Species:
†N. rietoogensis
Binomial name
†Namapoikia rietoogensis
Wood et al. 2002

The fossil was first found in the Omkyk Member of the Nama Group from Rietoog in southern Namibia, in association with other calcifying fossils, Cloudina and Namacalathus.

Its mineralogy and accretionary style has been compared with that of the Lophotrochozoans,[6] though its unfamiliar morphology suggests a stem-group or deeper affiliation to this group.[7]

It grew in spurts, first emplacing an organic skeleton, then filling this in with aragonite.[3]

See also

References
  1. Zhuravlev, A.Y., Wood, R.A., and Penny, A.M. (2015). Ediacaran skeletal metazoan interpreted as a lophophorate. Proc. R. Soc. B 282, 20151860. Available at: http://rspb.royalsocietypublishing.org/lookup/doi/10.1098/rspb.2015.1860.
  2. Susannah M. Porter (1 June 2007). "Seawater Chemistry and Early Carbonate Biomineralization". Science. 316 (5829): 1302. Bibcode:2007Sci...316.1302P. doi:10.1126/science.1137284. PMID 17540895.
  3. Wood, Rachel; Penny, Amelia (2018). "Substrate growth dynamics and biomineralization of an Ediacaran encrusting poriferan". Proceedings of the Royal Society B: Biological Sciences. 285 (1870): 20171938. doi:10.1098/rspb.2017.1938. PMC 5784191. PMID 29321296.
  4. Wood, Rachel A.; John P. Grotzinger; J. A. D. Dickson (28 June 2002). "Proterozoic Modular Biomineralized Metazoan from the Nama Group, Namibia". Science. 296 (5577): 2383–2386. Bibcode:2002Sci...296.2383W. doi:10.1126/science.1071599. PMID 12089440.
  5. Grotzinger, J.P.; Watters, W. A.; Knoll, A. H. (2000). "Calcified metazoans in thrombolite-stromatolite reefs of the terminal Proterozoic Nama Group, Namibia". Paleobiology. 26 (3): 334–359. doi:10.1666/0094-8373(2000)026<0334:CMITSR>2.0.CO;2.
  6. Zhuravlev, A. Y.; Wood, R. A.; Penny, A. M. (2015). "Ediacaran skeletal metazoan interpreted as a lophophorate". Proceedings of the Royal Society B: Biological Sciences. 282 (1818): 20151860. doi:10.1098/rspb.2015.1860. PMC 4650157. PMID 26538593.
  7. Zhuravlev, A. Yu.; Liñán, E. L.; Vintaned, J. A. Gámez; Debrenne, F.; Fedorov, A. B. (2012). "New finds of skeletal fossils in the terminal Neoproterozoic of the Siberian Platform and Spain". Acta Palaeontologica Polonica. 57: 205–224. doi:10.4202/app.2010.0074.


This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.