Xianguangia

Xianguangia is a soft-bodied sea anemone-like fossil animal from the Chengjiang Biota of China.[1]

Xianguangia
Scientific classification
Kingdom: Animalia
Phylum: incertae sedis
Genus: †Xianguangia
Species:
†X. sinica
Binomial name
†Xianguangia sinica
Chen & Erdtmann, 1991

Description

Xianguangia sinica has a cylindrical body with a whorl of nearly 16 tentacles around the oral disc, similar to the modern anthozoans. The tentacles are feather-like with dense pinnules on both sides of the axis which would have been well adapted to filter feeding. A bowl-shaped attachment disc at the basal part might commonly have been buried in the sediment to allow its sedentary strategy on the seafloor in life. The body above the pedal disc is broad and cylindrical and may correspond to the internal gastrovascular cavity. It displays several distinct longitudinal grooves and ridges on the surface, indicating possible mesenteries.[2] However, its phylogenetic affinity is still in question;[2] it has even been alleged to be related to members of the Ediacara biota.[3]

The fossils, found in Yunnan province, China, were initially described as three distinct species, Xianguangia sinica, Chengjian-gopenna wangii, and Galeaplumosus abilus, and then assembled into one proposed species, X. sinica. The animal was polyp-like, its gastric cavity divided by septa; it had a second body cavity in its holdfast, and densely-plumed feather-like tentacles, implying that it was a suspension feeder. Early cnidarians were probably also benthic suspension feeders, unlike later mainly predatory cnidarians.[4]

gollark: I would be somewhat annoyed if someone I was meeting with seemed to not care if I got infected or not.
gollark: Generally, if stuff gets written into law that way it ends up losing nuance.
gollark: Lots of stuff cannot particularly be done as WFH, so in most cases you probably cannot just stay home conveniently.
gollark: ... work?
gollark: Or feel socially pressured to because other people are, or just don't really know either way.

References
  1. Erwin, D. H.; Laflamme, M.; Tweedt, S. M.; Sperling, E. A.; Pisani, D.; Peterson, K. J. (2011). "The Cambrian Conundrum: Early Divergence and Later Ecological Success in the Early History of Animals". Science. 334 (6059): 1091–1097. doi:10.1126/science.1206375. PMID 22116879.
  2. Qian-Ping Leia; et al. (2013). "Sedentary habits of anthozoa-like animals in the Chengjiang Lagerstätte: Adaptive strategies for Phanerozoic-style soft substrates". Gondwana Research. In Press (3): 966–974. doi:10.1016/j.gr.2013.01.007.
  3. Han, J.; Kubota, S.; Uchida, H. O.; Stanley Jr, G. D.; Yao, X.; Shu, D.; Li, Y.; Yasui, K. (2010). Lalueza-Fox, Carles (ed.). "Tiny Sea Anemone from the Lower Cambrian of China". PLoS ONE. 5 (10): e13276. doi:10.1371/journal.pone.0013276. PMC 2954142. PMID 20967244.
  4. Ou, Qiang; Han, Jian; Zhang, Zhifei; Shu, Degan; Sun, Ge; Mayer, Georg (2017-07-31). "Three Cambrian fossils assembled into an extinct body plan of cnidarian affinity". Proceedings of the National Academy of Sciences. 114 (33): 8835–8840. doi:10.1073/pnas.1701650114. PMC 5565419. PMID 28760981.


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