Acosmia

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Acosmia
Temporal range: Chengjiang
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RCCBYU 10235 Acosmia maotiania.png
Fossil specimen
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Superphylum: Ecdysozoa
Genus: Acosmia
Chen & Zhoi 1997
Species:
A. maotiania
Binomial name
Acosmia maotiania
Chen & Zhoi 1997

Acosmia is an extinct genus of marine worm from the Cambrian aged Chengjiang biota of Yunnan, China. It is represented by a single rare species, Acosmia maotiania, that reached 45 mm in length and 9 mm in width. [1] It was likely a burrowing animal that fed by deposit feeding. [2] While originally suggested to be a priapulid (penis worm), a 2020 study proposed to be a stem-group ecdysozoan, due to lacking the radial pharygneal armature that characterises modern ecdysozoans, including priapulids. [2]

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References

  1. Hou, Xian-Guag; Aldridge, Richard; Bergstrom, Jan; Siveter, David J; Siveter, Derek; Feng, Xiang-Hong (2008-04-15). The Cambrian Fossils of Chengjiang, China: The Flowering of Early Animal Life. John Wiley & Sons. ISBN   9780470999943.
  2. 1 2 Howard, Richard J.; Edgecombe, Gregory D.; Shi, Xiaomei; Hou, Xianguang; Ma, Xiaoya (2020-11-23). "Ancestral morphology of Ecdysozoa constrained by an early Cambrian stem group ecdysozoan". BMC Evolutionary Biology. 20 (1): 156. Bibcode:2020BMCEE..20..156H. doi: 10.1186/s12862-020-01720-6 . ISSN   1471-2148. PMC   7684930 . PMID   33228518.