Vetulicola rectangulata Temporal range: | |
---|---|
Life restoration of Vetulicola rectangulata | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | † Vetulicolia |
Class: | † Vetulicolida |
Order: | † Vetulicolata |
Family: | † Vetulicolidae |
Genus: | † Vetulicola |
Species: | †V. rectangulata |
Binomial name | |
†Vetulicola rectangulata Luo and Hu, 1999 | |
Vetulicola rectangulata (meaning "rectangular ancient dweller") 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.
V. rectangulata was described by Luo Huilin and Hu Shi-xue of the Yunnan Institute of Biological Science in 1999. [1] [2] The fossils were discovered from the Early Cambrian Chengjiang deposits in Kunming region, Yunnan, China. [3]
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, [3] enclosed by a carapace-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. [4] 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. [5] Vetulicola rectangulata could be up to 7.2 cm long, and up to 3.7 cm in height (most specimens being 3.6 cm high). [6]
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. [7] At least one specimen has an individual of the putative entoproct, Cotyledion tyloides [8] attached to the terminal segment of the tail.
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.
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.
Cathaymyrus is a genus of Early Cambrian chordate known from the Chengjiang biota in Yunnan Province, China. Both species have a long segmented body with no distinctive head. The segments resemble the v-shaped muscle blocks found in cephalochordates such as Amphioxus. A long linear impression runs along the "back" of the body looking something like a chordate notochord.
Parapeytoia is a genus of Cambrian arthropod. The type and only described species is Parapeytoia yunnanensis, lived over 518 million years ago in the Maotianshan shales of Yunnan, China. Unidentified fossils from the same genus also had been discovered from the nearby Wulongqing Formation.
Diplopyge is genus of Cambrian arthropod known for being a member of the Chengjiang biota. It was described by Luo et al. in 1999.
Ercaicunia is genus of bivalved Cambrian arthropod from the Chengjiang biota of Yunnan, China. It contains a single species, E. multinodosa that was described by Luo et al. in 1999. The total length of the body ranges from 8 to 11 millimetres. The bivalved carapace covered about a third of the total body-length, and has up to six serrations on its forward edge. The head has a pair of large uniramous antennae, as well as a smaller pair of secondary antennae, as well as pair of mandibles and maxillae. The trunk has 16 pairs of biramous appendages. Specimens were CT scanned in 2019, which suggested it to be a stem-group crustacean. Other subsequent studies have recovered it as a member of Hymenocarina, which contains other bivalved Cambrian arthropods.
Isoxys is a genus of extinct bivalved Cambrian arthropod; the various species of which are thought to have been freely swimming predators. It had a pair of large spherical eyes, and two large frontal appendages used to grasp prey.
Jianshania is genus of Cambrian arthropod known from the Chengjiang biota, containing the single species J. furfactus. It was described by Luo et al. in 1999. In 2020, a specimen originally assigned to the species was found to represent the separate fuxianhuiid taxon Xiaocaris pending revision of the type specimen.
Archaeopriapulida is a group of priapulid worms known from Cambrian lagerstätte. The group is closely related to, and very similar to, the modern Priapulids. It is unclear whether it is mono- or polyphyletic. Despite a remarkable morphological similarity to their modern cousins, they fall outside of the priapulid crown group, which is not unambiguously represented in the fossil record until the Carboniferous. In addition to well-preserved body fossils, remains of several archaeopriapulid taxa are known to have been preserved primarily as organic microfossils, such as isolated scalids and pharyngeal teeth. They are probably closely related or paraphyletic to the palaeoscolecids; the relationship between these basal worms is somewhat unresolved.
The palaeoscolecids are a group of extinct ecdysozoan worms resembling armoured priapulids. They are known from the Lower Cambrian to the late Silurian; they are mainly found as disarticulated sclerites, but are also preserved in many of the Cambrian lagerstätten. They take their name from the typifying genus Palaeoscolex. Other genera include Cricocosmia from the Lower Cambrian Chengjiang biota. Their taxonomic affinities within Ecdysozoa have been the subject of debate.
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.
Zhongxiniscus is a genus of primitive chordate from eastern Yunnan that lived during the Early Cambrian. Known from a single specimen, it had a small, broad and short, fish-like body that was roughly ten millimeters in length. It possessed S-shaped myomeres, numbering roughly seven per one millimeter of length. Two triangular fins are evident on the dorsal margin.
Retifacies abnormalis is an extinct arthropod that lived in the lower Cambrian. Its fossil remains have been found in the Maotianshan Shales of Yunnan, China. It is a member of the Artiopoda, and closely related to Pygmaclypeatus.
Fuxianhuiida is an extinct clade of arthropods from the Cambrian of China. All currently known species are from Cambrian Series 2 aged deposits in Yunnan Province, including the Chengjiang biota. Although historically suggested to be members of the arthropod stem group recent research has suggested that they may be closely related to mandibulates. Many specimens are known with exceptional soft tissue preservation, including preserved guts and neural tissue, which given their basal phylogenetic position makes them important in understanding the evolution of Arthropoda as a whole. They reach a size of up to 15 cm, and are interpreted as benthic predators and scavengers. The Fuxianhuiid exoskeleton is unmineralised, and the number of tergites ranges from 15 to over 40. The cephalon is covered by a head shield and contains stalked eyes connected by the anterior sclerite, antennae, a butterfly shaped hyposome and a posterior facing mouth. Fuxianhuiids possess specialized post-antennal appendages with serrated edges used for food processing. The presence of gnathobases in members of Chengjiangocardidae suggests that they were capable of durophagy. In most Fuxianhuiids, the thorax tergites narrow posteriorly, terminating in either a swimming paddle or paired flukes with a tail spine. In members of Fuxianhuiidae the thorax is divided into two sections, the anterior wide opisthothorax and the posterior narrow limbless tail-like abdomen.
Guangweicaris is an extinct genus of fuxianhuiid arthropod known from the Cambrian period. It is only known from the type species Guangweicaris spinatus, which is known from the Cambrian Stage 4 Guanshan Biota near Kunming. It is currently the latest known fuxianhuiid. It was first described in 2007, and was given a comprehensive re-description in 2020. It is currently known from over 150 specimens. Within the fuxianhuiids it is sister to Fuxianhuia, together forming the clade Fuxianhuiidae. In comparison to Fuxianhuia it has a wide, oval shaped opisthothorax and a proportionally longer, narrow tail-like abdomen, with 3 prothoracic tergites, 5 opisthothoracic tergites and 7 abdominal tergites, it also possesses a row of spines running down the central axis of the body from the second opisthothoracic tergite.
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.
Lenisambulatrix is a genus of extinct worm belonging to the group Lobopodia and known from the Lower Cambrian Maotianshan shale of China. It is represented by a single species L. humboldti. The incomplete fossil was discovered and described by Qiang Ou and Georg Mayer in 2018. Due to its missing parts, its relationship with other lobopodians is not clear. It shares many structural features with another Cambrian lobopodian Diania cactiformis, a fossil of which was found alongside it.
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.