Talk:Xianguangia

Xianguangia is a Ediacaran survivor?

Han, J.; Kubota, S.; Uchida, H. O.; Stanley Jr, G. D.; Yao, X.; Shu, D.; Li, Y.; Yasui, K. (2010). "Tiny Sea Anemone from the Lower Cambrian of China". In Lalueza-Fox, Carles. PLoS ONE 5 (10)

Xianguangia sinica from the Lower Cambrian Chengjiang in China has been reported as a soft-bodied sea anemone [27], [44]. Observation on our new materials attributed to X. sinica has identified a holdfast and feather-like tentacles that have many long branches extending alternately from the tentacle axis. These features suggest that Xianguangia might be an Ediacaran survivor, a case similar to Stromatoveris [45], and thus its affinity to soft-bodied sea anemones [44] is difficult to accept.

1. Xianguangia has a actinia-like cylindrical body with 16 tentacles, such organisms are no among the Ediacaran fossils.
2. Feather-like TENTACLES of the Xianguangia is not frond-like BODY of a some Ediacaran organisms. In addition, many modern sea anemones and coral polyps have similar feather-like tentacles (for axample, Actinodendron, Phymanthus).
3. The Xianguangia has a typical for sea anemones pedal disc, NOT attachment disk with thin stem, such as Ediacaran Charniodiscus.
4. There is no reliable evidence of relationship between the Xianguangia, Stromatoveris and Ediacaran frond-like organisms.

Aleksey (Alnagov (talk) 16:15, 27 August 2013 (UTC))

I am sure that you are right: nevertheless, the article should still reflect the fact that the assertion has been made. A suitable phrasing might convey the scepticism with which the assertion might be handled... Martin (Smith609 – Talk) 21:24, 27 August 2013 (UTC)

You're right. Aleksey (Alnagov (talk) 06:52, 28 August 2013 (UTC))

And besides – at some level, Xianguanguia evolved from something that was alive in the Ediacaran! (Even if not a member of the traditional Ediacara Biota / Vendobionta) Martin (Smith609 – Talk) 21:25, 27 August 2013 (UTC)

As well as and others Cambrian organisms have Ediacaran ancestors that have not yet found. I don't like the term "Ediacara Biota", because it is artificial lopped term (biota is a set of all organisms of a specific locality or geological period, not a separate specieses), and "Vendobionta", because it is A. Seilachaer's biological taxon. During last year's expedition to the Ediacaran locality of the White Sea and in collection of the Paleontological Institute we have found reliable traces of a sea anemones (Bergaueria and other), traces of arthropods (Diplichnites trackway and Monomorphichnus), Oldhamia cf. curvata and others "Cambrian" traces. I will be describe these traces. My first article about new genus of the complex Ediacaran trace fossil will be published in the end 2014. Aleksey (Alnagov (talk) 06:52, 28 August 2013 (UTC))