''Vetulicola'' is an extinct genus of marine animal from the

Cambrian The Cambrian Period ( ; sometimes symbolized C with bar, Ꞓ) was the first geological period of the Paleozoic Era, and of the Phanerozoic Eon. The Cambrian lasted 53.4 million years from the end of the preceding Ediacaran Period 538.8 million ...

China China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and ...

. It is the eponymous member of the enigmatic phylum Vetulicolia, which is of uncertain affinities but may belong to the

deuterostome Deuterostomia (; in Greek) are animals typically characterized by their anus forming before their mouth during embryonic development. The group's sister clade is Protostomia, animals whose digestive tract development is more varied. Some exampl ...

Description

The type species, ''Vetulicola cuneata'' (Hou, 1987) has a body composed of two distinct parts of approximately equal length. The anterior part is rectangular with a

carapace A carapace is a Dorsum (biology), dorsal (upper) section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tor ...

-like structure of four rigid cuticular plates, with a large mouth at the front end. The posterior section is slender, strongly cuticularised and placed dorsally. Paired openings connecting the pharynx to the outside run down the sides. These features are interpreted as possible primitive gill slits. ''Vetulicola cuneata'' could be up to 9 cm long. The ''Vetulicola'' are thought to have been swimmers that were either

filter feeder Filter feeders are a sub-group of suspension feeding animals that feed by straining suspended matter and food particles from water, typically by passing the water over a specialized filtering structure. Some animals that use this method of feedin ...

s or

detritivore Detritivores (also known as detrivores, detritophages, detritus feeders, or detritus eaters) are heterotrophs that obtain nutrients by consuming detritus (decomposing plant and animal parts as well as feces). There are many kinds of invertebrates, ...

s. Other ''Vetulicola'' species described are ''Vetulicola rectangulata'' (Luo & Hou, 1999), ''V. gantoucunensis'' (Luo et al., 2005), ''V. monile'' (Aldridge, Hou, Siveter, Siberet and Gabbott, 2007), and ''V. longbaoshanensis''. The mouth openings of all the other species are smaller, and do not protrude as in ''V. cuneata''. All other species, with the stark exception of ''V. gantoucunensis'', are smaller than the type species.

Taxonomy

''Vetulicolas

taxonomic Taxonomy is the practice and science of categorization or classification. A taxonomy (or taxonomical classification) is a scheme of classification, especially a hierarchical classification, in which things are organized into groups or types. ...

position is controversial. ''Vetulicola cuneata'' was originally assigned to the crustaceans on the assumption that it was a bivalved arthropod like '' Canadaspis'' and '' Waptia'', but the lack of legs, the presence of gill slits, and the four plates in the "carapace" were unlike any known arthropod. Shu ''et al.'' placed ''Vetulicola'' in the new family Vetulicolidae,

order Order, ORDER or Orders may refer to: * Categorization, the process in which ideas and objects are recognized, differentiated, and understood * Heterarchy, a system of organization wherein the elements have the potential to be ranked a number of d ...

Vetulicolida and

phylum In biology, a phylum (; plural: phyla) is a level of classification or taxonomic rank below kingdom and above class. Traditionally, in botany the term division has been used instead of phylum, although the International Code of Nomenclature f ...

Vetulicolia, among the

s. Shu (2003) later argued that the vetulicolians were an early, specialized side-branch of deuterostomes. Dominguez and Jefferies classify ''Vetulicola'' as an urochordate, and probably a stem-group appendicularian. In contrast, Butterfield places ''Vetulicola'' among the arthropods. The discovery of the related Australian vetulicolian ''

Nesonektris ''Nesonektris aldridgei'' is an extinct deuterostome chordate from the Late Botomian-aged Emu Bay Shale Lagerstätte in Kangaroo Island, Australia. So far, it is the fourth described vetulicolian that is not restricted to the Maotianshan ...

'', from the Lower Cambrian Emu Bay Shale of Kangaroo Island, and the reidentification of the "coiled gut" of vetulicolians as being a notochord affirms the identification as an urochordate.

Etymology

''Vetulicola'' is a compound Latin word composed of ''vetuli'', meaning "old," or "ancient," and ''cola'', meaning "inhabitant.""Vetulicolians - are they deuterostomes? chordates?"
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Paleobiology

''Vetulicola'' was the host of the

symbiotic Symbiosis (from Greek , , "living together", from , , "together", and , bíōsis, "living") is any type of a close and long-term biological interaction between two different biological organisms, be it mutualistic, commensalistic, or parasit ...

organism '' Vermilituus gregarius'', which appears to have lived inside ''Vetulicolas anterior body. Only around 2% of ''Vetulicola'' individuals had ''Vermilituus'' infestations, but ''Vermilituus'' could be very numerous: one ''Vetulicola'' specimen had 88 individuals of ''Vermilituus'' infesting it. Such large numbers of symbiotic organisms were probably harmful to the host ''Vetulicola''.

References

*Butterfield, Nicholas J. 2003. Exceptional Fossil Preservation and the Cambrian Explosion. ''Integrative and Comparative Biology''. 43(1):166-177

- URL retrieved June 22, 2006 *Dominguez, Patricio and Jefferies, Richard. 2003. Fossil evidence on the origin of appendicularians. International Urochordate Meeting 2003. Abstract a

- URL retrieved June 22, 2006 *LUO, Huilin, FU, Xiaoping, HU, Shixue, LI, Yong, CHEN, Liangzhong, YOU, Ting and LIU, Qi. 2005. New Vetulicoliids from the Lower Cambrian Guanshan Fauna,

Kunming Kunming (; ), also known as Yunnan-Fu, is the capital and largest city of Yunnan province, China. It is the political, economic, communications and cultural centre of the province as well as the seat of the provincial government. The headquar ...

. Abstract a

- URL retrieved June 30, 2008 *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). Abstract a

- URL retrieved June 30, 2008 *Shu, Degan. 2003. A paleontological perspective of vertebrate origin. ''Chinese Science Bulletin'', Vol. 48 No. 8 725-735. April, 2003. Abstract a

- URL retrieved June 30, 2008

External links

Biota of the Maotianshan Shale, Chengjiang China
- URL retrieved June 22, 2006 * Palaeos' Page on Vetulicoliabr>Photos of ''Vetulicola cuneata'' fossils
- URL retrieved June 22, 2006

- Accessed January 3, 2008

- Accessed January 3, 2008 {{Taxonbar, from=Q7923847 Vetulicolia Maotianshan shales fossils Cambrian genus extinctions