Vetulicolia

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Vetulicolia
Fossil range: Cambrian

Scientific classification

Kingdom:	Animalia
Superphylum:	?Deuterostomia
Phylum:	Vetulicolia Shu, et al. 2001

Classes

Vetulicolia is an extinct phylum erected by Shu et al. (2001), encompassing several early-Cambrian fossil forms. They suggest that these animals were early deuterostomes. The bodyplan consists of two parts, a voluminous anterior section with a large "mouth" and a row of five round to oval-shaped features on each side that are interpreted as gills (or at least openings in the vicinity of the pharynx) and a posterior section with seven segments. The area where the anterior and posterior parts join is constricted. The phylum Vetulicolia is defined by Shu et al. to include the family Didazoonidae, with the genera Didazoon and Xidazoon, the family Vetulicolidae, with the genera Pomatrum, Vetulicola, and Banffia. The authors also propose that vetulicolians and yunnanozoans may be closely related.

Shu (2003) has argued that the vetulicolians probably represent an early specialized side-branch of deuterostomes, and that this implies that segmentation in cephalochordates and vertebrates may be derived from the common ancestor of protostomes and deuterostomes. Briggs et al. (2005) described Skeemella from the Middle Cambrian of Utah as having affinity to Vetulicolia, but also as having arthropod features, thus confounding assignment of Vetulicolia to Deuterostomia. Dominguez and Jefferies have argued, based on morphological analysis, that Vetulicola (and by implication, other Vetulicolians) is a urochordate, and probably a stem-group larvacean. The taxonomic placement of the Vetulicolians remains controversial.

1 Etymology
2 Classification
3 References
4 External links

Etymology

The phylum name, Vetulocolia, is derived from the type genus, Vetulicola, which is a compound Latin word composed of vetuli, or "old," and cola, or "inhabitant."^[1]

Classification

This section does not cite any references or sources.
Please help improve this section by adding citations to reliable sources. Unverifiable material may be challenged and removed. (March 2007)

Phylum Vetulicolia
- Class Vetulicolida
  - Order Vetulicolata
    - Family Vetulicolidae
      - Genus Vetulicola
        
        Vetulicola rectangulata
        
        Vetulicola cuneata
        
        Vetulicola gangtoucunensis
    - Family Beidazooidae
      - Genus Beidazoon
        
        Beidazoon venustum (synonym = Bullivetula variola)
    - Family Didazoonidae
      - Genus Didazoon
        
        Didazoon haoae
      - Genus Xidazoon
        
        Xidazoon stephanus
  - ?Order Yunnanozoa
    - Family Yunnanozoonidae
      - Genus Yunnanozoon
        
        Yunnanozoon lividum
      - Genus Haikouella
        
        Haikouella lanceolata
- Class Banffozoa
  - - - Skeemella clavula
    - Family Banffiidae
      - Genus Banffia
        
        Banffia constricta^[2]
- Class Heteromorphida
  - - Family Heteromorphidae
      - Genus Heteromorphus
        
        Heteromorphus longicaudatus (synonym=Banffia confusa)
        
        "Form A" (unnamed species)
incertae sedis Yuyuanozoon magnificissimi ^[3]

References

Shu, D.-G., Conway Morris, S., Han, J., Chen, L., Zhang, X.-L., Zhang, Z.-F., Liu, H.-Q., Li, Y., and Liu, J.-N. 2001. Primitive Deuterostomes from the Chengjiang Lagerstätte (Lower Cambrian, China), Nature, 414:419-424. (November 11, 2001). [1].
Briggs, D., Lieberman, B., Halgedahl, S. and Jarrard, R. (2005), A new metazoan from the Middle Cambrian of Utah and the nature of Vetulicolia. Palaeontology 48: 681-686.
Shu, Degan. 2003. A paleontological perspective of vertebrate origin. Chinese Science Bulletin, Vol. 48 No. 8 725-735. April, 2003. [2] - URL retrieved June 22, 2006
Dominguez, Patricio and Jeffries, Richard. (2003). Fossil evidence on the origin of appendicularians. Paper read at International Urochordate Meeting 2003. Abstract at [3] - URL retrieved June 22, 2006