''Vetulicola rectangulata'' ("Rectangular ancient dweller") is a species of small, Early

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 ...

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 ...

animals from the

Chengjiang biota The Maotianshan Shales are a series of Early Cambrian deposits in the Chiungchussu Formation, famous for their '' Konservat Lagerstätten'', deposits known for the exceptional preservation of fossilized organisms or traces. The Maotianshan Shales ...

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 ...

Description

Like ''V. cuneata,'' ''V. rectangulata'' has a body composed of two distinct parts of approximately equal length. The anterior part is oval to rectangular in shape, enclosed by 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 fused together, with a small mouth at the front end: there is a keel-like extension of the body wall on the top and belly. Unlike in ''V. cuneata'', the mouth region does not protrude out. The tail-like 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 rectangulata'' could be up to 7 cm long, and up to 4 cm in height (most specimens being 3.6 cm high).

Lifestyle

It is assumed that ''V. rectangulata'' spent most or all of its time swimming in the water column. Sediment found within the gut suggest that it was a deposit-feeder, possibly swimming to and from favorable feeding sites. At least one specimen has an individual of the putative entoproct, ''

Cotyledion tyloides ''Cotyledion tylodes'' is an extinct, stalked filter-feeder known from the Chengjiang lagerstatten. The living animal reached a couple of centimetres in height, and bore a loose scleritome of ovoid sclerites. Its interpretation has been con ...

'' attached to the terminal segment of the tail.

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 {{Taxonbar, from=Q17104101 Vetulicolia Fossil taxa described in 1999