Vetulicola Temporal range: | |
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Vetulicola rectangulata and V. cuneata | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | † Vetulicolia |
Class: | † Vetulicolida |
Order: | † Vetulicolata |
Family: | † Vetulicolidae |
Genus: | † Vetulicola Hou, 1987 |
Type species | |
Vetulicola cuneata Hou, 1987 | |
Species | |
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Vetulicola is an extinct genus of marine animal discovered from the Cambrian of China. It is the eponymous member of the enigmatic phylum Vetulicolia, which is of uncertain affinities but may belong to the deuterostomes. The name was derived from Vetulicola cuneata, the first species described by Hou Xian-guang in 1987 from the Lower Cambrian Chiungchussu Formation in Chengjiang, China. [1] [2]
The type species, Vetulicola cuneata, as originally described by Hou Xian-guang in 1987, has a body plan similar to those of arthropods and composed of two distinct parts of approximately equal length. [3] The anterior part is rectangular with a carapace-like structure of four rigid cuticular plates, with a large mouth at the front end. [4] 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 possible filter feeders. [5]
Other Vetulicola species described are Vetulicola rectangulata (Luo and Hu, 1999), V. gantoucunensis (Luo et al., 2005), V. monile (Aldridge et al., 2007), and V. longbaoshanensis (Yang et al., 2010). 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.
Vetulicola's taxonomic position is controversial. V. cuneata was originally assigned to the phylum Arthropoda on the assumption that it was a bivalved arthropod like Canadaspis and Waptia , [3] but the lack of legs, the presence of gill slits, and the four plates in the "carapace" were unlike any known arthropod. [6] In 2001, Degan Shu and his team reinterpreted the animals as deuterostomes placing Vetulicola in the new family Vetulicolidae, order Vetulicolida, and created a new phylum Vetulicolia. [7]
Shu later in 2003 argued that the vetulicolians were an early, specialized side-branch of deuterostomes. [8] Patricio Dominguez and Richard Jefferies classify Vetulicola as an urochordate, and probably a stem-group appendicularian. [9] In contrast, Nicholas J. Butterfield places Vetulicola among the arthropods. [10] The discovery of the related Australian vetulicolian Nesonektris , 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. [11]
Vetulicola is a compound Latin word composed of vetuli, meaning "old," or "ancient," and cola, meaning "inhabitant." [7] [12]
Vetulicola was the host of the symbiotic organism Vermilituus gregarius , which appears to have lived inside Vetulicola's 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. [5]
Vetulicolia is a phylum of bilaterian animals encompassing several extinct species belonging to the Cambrian period. The phylum was created by Degan Shu and his research team in 2001, and named after Vetulicola cuneata, the first species of the phylum described in 1987.
The Maotianshan Shales (帽天山页岩) are a series of Early Cambrian sedimentary deposits in the Chiungchussu Formation, famous for their Konservat Lagerstätten, deposits known for the exceptional preservation of fossilized organisms or traces. The Maotianshan Shales form one of some forty Cambrian fossil locations worldwide exhibiting exquisite preservation of rarely preserved, non-mineralized soft tissue, comparable to the fossils of the Burgess Shale of British Columbia, Canada. They take their name from Maotianshan Hill in Chengjiang County, Yunnan Province, China.
Yunnanozoon lividum is an extinct species of bilaterian animal from the Lower Cambrian Chengjiang biota of Yunnan province, China. Its affinities have been long the subject of controversy.
Didazoon haoae is an extinct species of vetulicolid vetulicolian described by Shu, et al. based on fossils found in the Qiongzhusi (Chiungchussu) Formation, Yu'anshan Member, Lower Cambrian, in the Dabanqiao area (Kunming), about 60 km northwest of Chengjiang, China.
Pomatrum is an extinct vetulicolian, the senior synonym of Xidazoon; the latter taxon was described by Shu, et al. (1999) based on fossils found in the Qiongzhusi (Chiungchussu) Formation, Yu'anshan Member, Lower Cambrian, Haikou, (Kunming), about 50 km west of Chengjiang, China. It has been likened to the chordate Pipiscius.
Banffia is a genus of animals described from Middle Cambrian fossils. The genus commemorates Banff, Alberta, near where the first fossil specimens were discovered. Its placement in higher taxa is controversial. It is considered to be a member of the enigmatic phylum Vetulicolia.
Leanchoilia is a megacheiran arthropod known from Cambrian deposits of the Burgess Shale in Canada and the Chengjiang biota of China.
Deuterostomes are bilaterian animals of the superphylum Deuterostomia, typically characterized by their anus forming before the mouth during embryonic development. Deuterostomia is further divided into 4 phyla: Chordata, Echinodermata, Hemichordata, and the extinct Vetulicolia known from Cambrian fossils. The extinct clade Cambroernida is also thought to be a member of Deuterostomia.
Haikoucaris is a genus of megacheiran arthropod that contains the single species Haikoucaris ercaiensis. It was discovered in the Cambrian Chengjiang biota of China.
Kunmingella is genus of Cambrian bradoriid from the Chengjiang biota, containing the single species K. douvillei. Kunmingella had 12 appendages, including a pair of antennae as well pairs of biramous limbs, including four anterior pairs of appendages bearing double rows of endites on their endopods, and a posterior 5 with only a single row of endites, as well as two terminal pairs of uniramous limbs. Eggs have been found preserved attached to the posteriormost three pairs of biramous limbs, suggesting it engaged in brood care. Around 50–80 eggs, each around 150–180 μm across were attached in total.
Vetulicola cuneata is a species of extinct animal from the Early Cambrian Chengjiang biota of China. It was described by Hou Xian-guang in 1987 from the Lower Cambrian Chiungchussu Formation, and became the first animal under an eponymous phylum Vetulicolia.
Cucumericrus ("cucumber-leg") is an extinct genus of stem-arthropod. The type and only species is Cucumericrus decoratus, with fossils discovered from the Maotianshan Shales of Yunnan, China.
Ooedigera peeli is an extinct vetulicolian from the Early Cambrian of North Greenland. The front body was flattened horizontally, oval-shaped, likely bearing a reticulated or anastomosing pattern, and had 5 evenly-spaced gill pouches along the midline. The tail was also bulbous and flattened horizontally, but was divided into 7 plates connected by flexible membranes, allowing movement. Ooedigera likely swam by moving side-to-side like a fish. It may have lived in an oxygen minimum zone alongside several predators in an ecosystem based on chemosynthetic microbial mats, and was possibly a deposit or filter feeder living near the seafloor.
Skeemella clavula is an elongate animal from what is now the Middle Cambrian Wheeler Shale and Marjum lagerstätte of Utah. It has been classified with the vetulicolians.
Vetulicola rectangulata is a species of extinct animal from the Early Cambrian of the Chengjiang biota of China. Regarded as a deuterostome, it has characteristic rectangular anterior body on which the posterior tail region is attached. It was described by Luo Huilin and Hu Shi-xue in 1999.
Beidazoon venustum is a deuterostome from the deuterostome group Vetulicolia. It originates from the lower Cambrian Chengjiang biota of Yunnan Province, China. Beidazoon was a marine organism discovered by Degan Shu in 2005.
Vetulocystidae is the only family of the taxon Vetulocystida, which is a group of extinct deuterostomes of uncertain phylogenetic position. Vetulocystidae is made up of the genera Vetulocystis, Dianchicystis and Thylacocercus.
Luolishania is an extinct genus of lobopodian panarthropod and known from the Lower Cambrian Chiungchussu Formation of the Chengjiang County, Yunnan Province, China. A monotypic genus, it contains one species Luolishania longicruris. It was discovered and described by Hou Xian-Guang and Chen Jun-Yuan in 1989. It is one of the superarmoured Cambrian lobopodians suspected to be either an intermediate form in the origin of velvet worms (Onychophora) or basal to at least Tardigrada and Arthropoda. It is the basis of the family name Luolishaniidae, which also include other related lobopods such as Acinocricus, Collinsium, Facivermis, and Ovatiovermis. Along with Microdictyon, it is the first lobopodian fossil discovered from China.
The Cambrian chordates are an extinct group of animals belonging to the phylum Chordata that lived during the Cambrian, between 538 and 485 million years ago. The first Cambrian chordate known is Pikaia gracilens, a lancelet-like animal from the Burgess Shale in British Columbia, Canada. The discoverer, Charles Doolittle Walcott, described it as a kind of worm (annelid) in 1911, but it was later identified as a chordate. Subsequent discoveries of other Cambrian fossils from the Burgess Shale in 1991, and from the Chengjiang biota of China in 1991, which were later found to be of chordates, several Cambrian chordates are known, with some fossils considered as putative chordates.
Hou Xian-guang is a Chinese paleontologist at Yunnan University who made key discoveries in the Cambrian life of China around 518 myr. His first discovery of animal fossils from the Cambrian sediments at Chengjiang County, Yunnan Province, led to the establishment of the Chengjiang biota, an assemblage of various life forms during the Cambrian Period. The discovery of the Chengjiang biota, remarked as "among the most spectacular in this [20th] century", added to the better understanding of how animal forms originated and evolved during the so-called Cambrian explosion.