''Vetulicola'' is an extinct

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

of marine animal from the Cambrian of China. It is the eponymous member of the enigmatic phylum

Vetulicolia VetulicoliaThe taxon name, Vetulocolia, is derived from the type genus, ''Vetulicola'', which is a compound Latin word composed of ''vetuli'' "old" and ''cola'' "inhabitant". is a taxon (either phylum or subphylum in rank) encompassing several ex ...

, which is of uncertain affinities but may belong to the deuterostomes.

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-like structure of four rigid

cuticular A cuticle (), or cuticula, is any of a variety of tough but flexible, non-mineral outer coverings of an organism, or parts of an organism, that provide protection. Various types of "cuticle" are non- homologous, differing in their origin, structu ...

plates, with a large mouth at the front end. The posterior section is slender, strongly cuticularised and placed

dorsal Dorsal (from Latin ''dorsum'' ‘back’) may refer to: * Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism * Dorsal, positioned on top of an aircraft's fuselage * Dorsal c ...

ly. Paired openings connecting the

pharynx The pharynx (plural: pharynges) is the part of the throat behind the mouth and nasal cavity, and above the oesophagus and trachea (the tubes going down to the stomach and the lungs). It is found in vertebrates and invertebrates, though its st ...

to the outside run down the sides. These features are interpreted as possible primitive

gill slit Gill slits are individual openings to gills, i.e., multiple gill arches, which lack a single outer cover. Such gills are characteristic of cartilaginous fish such as sharks and rays, as well as deep-branching vertebrates such as lampreys. In con ...

s. ''Vetulicola cuneata'' could be up to 9 cm long. The ''Vetulicola'' are thought to have been swimmers that were either filter feeders or detritivores. 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 position is controversial. ''Vetulicola cuneata'' was originally assigned to the

crustacean Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group can ...

s 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 Arthropods (, (gen. ποδός)) are invertebrate animals with an exoskeleton, a segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and cuticle made of chiti ...

. Shu ''et al.'' placed ''Vetulicola'' in the new

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Vetulicolidae, order Vetulicolida and phylum

, among the deuterostomes. Shu (2003) later argued that the vetulicolians were an early, specialized side-branch of deuterostomes. Dominguez and Jefferies classify ''Vetulicola'' as an

urochordate A tunicate is a marine invertebrate animal, a member of the subphylum Tunicata (). It is part of the Chordata, a phylum which includes all animals with dorsal nerve cords and notochords (including vertebrates). The subphylum was at one time c ...

, and probably a stem-group appendicularian. In contrast, Butterfield places ''Vetulicola'' among the arthropods. The discovery of the related Australian vetulicolian '' Nesonektris'', from the Lower Cambrian

Emu Bay Shale The Emu Bay Shale is a geological formation in Emu Bay, South Australia, containing a major Konservat-Lagerstätte (fossil beds with soft tissue preservation). It is one of two in the world containing Redlichiidan trilobites. The 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?"
/ref>

Paleobiology

''Vetulicola'' was the host of the symbiotic 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. 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 Palaeos.com is a web site on biology, paleontology, phylogeny and geology and which covers the history of Earth. The site is well respected and has been used as a reference by professional paleontologists such as Michael J. Benton, the professor of ...

' Page on

br>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