Vetulicolia

Vetulicolia
Vetulicolia
Temporal occurrence
Lower Cambrian to Middle Cambrian
525 to 505 million years
Locations
Chengjiang Faunal Community , People's Republic of China Burgess Shale , Canada
Systematics
without rank: Holozoa without rank: Multicellular animals (Metazoa) without rank: Tissue animals (Eumetazoa) without rank: Bilateria Over trunk : Neumünder (Deuterostomia) Trunk : Vetulicolia
Scientific name
Vetulicolia
Shu et al. , 2001

Vetulicolia is the name of an extinct animal strain that Shu et al. a. was created; it includes several sub-Cambrian fossil forms. The taxonomic allocation of the Vetulicolia is controversial according to the current state of science (2008). DG Shu et al. advocate that these animals are early new mouths (Deuterostomia). Its construction plan consists of two parts: a voluminous front part with a large "mouth", which is followed by a row of five round to oval openings on both sides - possibly these are gill slits or breathing holes located near the pharynx - and one made up of seven segments existing rump. The section between the front and rear is narrowed. According to Shu et al. a. the tribe Vetulicolia includes the family Didazoonidae with the genera Didazoon and Xidazoon , the family Vetulicolidae with the genera Pomatrum and Vetulicola and the genus Banffia . The authors also take the view that the tribe of the Vetulicolia is closely related to that of the Yunnanozoa .

In his work from 2003, Shu takes the position that the Vetulicolia represent a side branch of the Deuterostomia, which had specialized early on. This in turn gives rise to the conclusion that the division into cephalochordata and vertebrata can possibly be traced back to the common ancestors of the protostomia and the deuterostomia. Briggs et al. a. described the species Skeemella clavula from the middle Cambrian of Utah in 2005 ; it shows a certain affinity to the Vetulicolia, but at the same time has characteristics of the Arthropoda and thus questions an assignment of the Vetulicolia to the Deuterostomia. For Dominguez and Jefferies, on the other hand, based on morphological studies , the Vetulicolia are to be regarded as Urochordata , possibly they are a stem group of the Larvacea . All possible family positions are discussed in a paper by Aldrige et al. referred to in detail without a definitive assignment being possible.

Finds of Vetulicolia in the South Australian Emu Bay Shale - fossil deposit revealed a new genus Nesonektris . It not only expands the previously known distribution, but also provides new arguments for belonging to the tunicates within the Chordata tribe through a clearly recognizable longitudinal structure, which is interpreted as a notochord .

Systematic position

• Vetulicolia tribe
  • Class Vetulicolia
    • Order Vetulicolida
      • Family Vetulicolidae
        • Genus Vetulicola
          • Vetulicola rectangulata
          • Vetulicola cuneata
          • Vetulicola gangtoucunensis
        • Genus Banffia
          • Banffia constricta
          • Banffia confusa
      • Family Didazoonidae
        • Genus Didazoon
          • Didazoon haoae
        • Genus Xidazoon
          • Xidazoon stephanus
    • ? Okay Yunnanozoa
      • Family Yunnanozoonidae
        • Genus Yunnanozoon
          • Yunnanozoon lividum

without family assignment ( incertae sedis ):

• Genus Nesonektris
  • Nesonektris aldridgei

swell

1. ↑ ^{a b} D.-G. Shu, S. Conway Morris , J. Han, L. Chen, X.-L. Zhang, Z.-F. Zhang, H.-Q. Liu, Y. Li and J.-N. Liu: Primitive Deuterostomes from the Chengjiang Deposit (Lower Cambrian, China) , Nature, 414: 419-424. (November 11, 2001).
2. ↑ Degan Shu: A paleontological perspective of vertebrate origin . Chinese Science Bulletin, Vol. 48 No. 8 725-735. April, 2003.
3. ^ D. Briggs, B. Lieberman, S. Halgedahl and R. Jarrard: A new metazoan from the Middle Cambrian of Utah and the nature of Vetulicolia . Palaeontology, July 2005, Volume 48 Issue 4, pages 681-686. doi : 10.1111 / j.1475-4983.2005.00489.x
4. ^ Patricio Dominguez and Richard Jeffries: Fossil evidence on the origin of appendicularians. Presented at the International Urochordate Meeting 2003, Carry le Rouet, France.
5. ^ RJ Aldrige, H. Xian-Guang, JD Siveter, DJ Siveter, SE Gabbott (2007): The systematics and phylogenetic relationships of Vetulicolians. Palaeontology 50: 131-168. doi : 10.1111 / j.1475-4983.2006.00606.x (open access)
6. ^ ^{A b} García-Bellido, DC, Lee, MSY, Edgecombe, GD, Jago, JB, Gehling, JG, Paterson, JR (2014): A new vetulicolian from Australia and its bearing on the chordate affinities of an enigmatic Cambrian group. BMC Evolutionary Biology, 14, 214. doi : 10.1186 / s12862-014-0214-z (open access)

Web links

Commons : Vetulicolia  - collection of images, videos and audio files

• New phylum on the block ( February 18, 2007 memento on the Internet Archive ) - Retrieved January 3 , 2008
• Photos and drawings of fossils of various Vetulicolians - Retrieved January 3 , 2008