| Sinocylindra Temporal range: | |
|---|---|
 | |
| Fossilized specimen of Sinocylindra | |
Scientific classification  | |
| Clade: | Viridiplantae |
| Division: | Chlorophyta |
| Genus: | † Sinocylindra Chen and Erdtmann, 1991 |
Sinocylindra is an extinct genus of macroalgae that existed between the Ediacaran and Middle Cambrian periods. It is a part of the Chengjiang biota in the Maotianshan Shales in Yunnan, China. Only two species, S. yunnanensis and S. linearis, are described.
Sinocylindra yunnanensis was a cylindrical macroalgae 0.2-0.35 mm wide, that could reach up to 20-40 mm long. [1] Its surface is smooth, and it was likely flexible, as specimens have been found coiled and curved. [2] [3] It was previously thought by some that S. yunnanensis might be a prokaryotic species in the Siphonophycus genus, [4] however due to elements of its morphology such as the size and length of the species, it was determined to most likely be a eukaryotic algae of a previously unknown genus. [1] S. yunnanensis lived roughly between 635-516 million years ago. [5]
Sinocylindra linearis, like yunnanensis, was cylindrical in shape, with a diameter ranging from 0.3-2.0mm, and a length of 5.0-50 mm. [2] It was probably firmer and less flexible than yunnanensis as some specimens found were almost completely straight. [2]
Sinocylindra yunnanensis was first described in 1991, found in the Upper Doushantuo shales at Chengjiang, in the Chinese province of Yunnan. [1] Since its discovery, a number of fossils across Southern China have been found, as well as a specimen in the Drumian Marjum formation in Utah, United States. [6]
Sinocylindra linearis was described by researchers in 2017 after being found in the Ediacaran Miaohe member in southern China, [7] where one hundred and twenty-eight specimens were found. [2] The name linearis was given due to the straight, rigid nature of the species.
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.
Dickinsonia is a genus of extinct organism, most likely an animal, that lived during the late Ediacaran period in what is now Australia, China, Russia, and Ukraine. It is one of the best known members of the Ediacaran biota. The individual Dickinsonia typically resembles a bilaterally symmetrical ribbed oval. Its affinities are presently unknown; its mode of growth has been considered consistent with a stem-group bilaterian affinity, though various other affinities have been proposed. It lived during the late Ediacaran. The discovery of cholesterol molecules in fossils of Dickinsonia lends support to the idea that Dickinsonia was an animal, though these results have been questioned.
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.
Swartpuntia is a monospecific genus of erniettomorph from the terminal Ediacaran period, with at least three quilted, leaf-shaped petaloids — probably five or six. The petaloids comprise vertical sheets of tubes filled with sand. Swartpuntia specimens range in length from 12 to 19 cm, and in width from 11.5 to 140 cm. The margin is serrated, with a 1 mm wide groove. A 14 mm wide stem extends down the middle, tapering towards the top, and stopping 25 mm from the tip. The stem has a V-shaped ornamentation on it. The original fossils were found at, and named after, the Swartpunt farm between Aus and Rosh Pinah in Namibia. The generic name comes from Swartpunt, meaning black point in reference to the colour of the rocks. The specific name germsi honours Gerard Germs, who studied the Nama formation of geological beds.
The Kaili Formation is a stratigraphic formation which was deposited during the Lower and Middle Cambrian. The formation is approximately 200 metres (660 ft) thick and was named after the city Kaili in the Guizhou province of southwest China.
Dinomischusis an extinct genus of stalked filter-feeding animals within the Cambrian period, with specimens known from the Burgess Shale and the Maotianshan Shales. While long of uncertain affinities, recent studies have suggested it to be a stem-group ctenophore.
Saperion is an extinct genus of trilobite-like arthropod. It lived during the late Atdabanian stage, which lasted from 521 to 514 million years ago during the early part of the Cambrian Period. It was found in the Maotianshan Shales of Yunnan, China. Similar to the closely-related Skioldia and Tegopelte, the head shield and trunk tergites were fused into a single plate. There are about 19 furrows indicating the original trunk segments. a small anterior sclerite articulated to the front of its head. A pair of antennae and lateral eyes located ventrally behind the anterior sclerite, lateral to the hypostome. Saperion reached 151 mm in length and had nearly 25 pairs of biramous limbs for walking.
Eoandromeda is an Ediacaran organism consisting of eight radial spiral arms, and known from two taphonomic modes: the standard Ediacara type preservation in Australia, and as carbonaceous compressions from the Doushantuo formation of China, where it is abundant.
Yuyuanozoon magnificissimi, from the Cambrian Stage 3 Chengjiang lagerstatte, is the largest known vetulicolian, with specimens up to 20 cm in length compared to 5–14 cm for other vetulicolian species.
This is a list of fossils found at Maotianshan Shales, whose most famous assemblage of organisms are referred to as the Chengjiang biota.
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.
Pectocaris is an extinct genus of bivalved arthropods from the Cambrian Maotianshan Shales, Yunnan Province of China. There are currently four known species within the genus.
Primicaris is genus of Cambrian arthropod from the Chengjiang biota of China and the Burgess Shale of Canada. It contains a single described species, P. larvaformis.
Pseudoiulia is a genus of Cambrian arthropod known from the Chengjiang Biota of Yunnan, China, containing the single species P. cambriensis. It is considered poorly known, but has been somewhat associated with other Chengjiang Biota fauna such as Dongshania folliformis and Pissinocaris subconigera. In 2013, Pseudoiulia was suggested to be a member of the family Kootenichelidae, alongside Kootenichela and Worthenella.
Cambrorhytium is an enigmatic fossil genus known from the Latham Shale (California), and the Chengjiang (China) and Burgess Shale lagerstätte. 350 specimens of Cambrorhytium are known from the Greater Phyllopod bed, where they comprise 0.7% of the community.
Squamacula is an extinct artiopodan arthropod from the Cambrian Series 2. The type species S. clypeata was described in 1997 from the Chengjiang biota of Yunnan, China. At the time of description there were only two known specimens of S. clypeata, but now there are at least six known specimens. In 2012 a second species S. buckorum was described from the Emu Bay Shale of Australia.
Houcaris is a possibly paraphyletic radiodont genus, tentatively assigned to either Amplectobeluidae, Anomalocarididae or Tamisiocarididae, known from Cambrian Series 2 of China and the United States. The type species is Houcaris saron which was originally described as a species of the related genus Anomalocaris. Other possible species include H. magnabasis and H. consimilis. The genus Houcaris was established for the two species in 2021 and honors Hou Xianguang, who had discovered and named the type species Anomalocaris saron in 1995 along with his colleagues Jan Bergström and Per E. Ahlberg.
Calyptrina striata is an Ediacaran tubular fossil, probably belonging to some kind of tube-dwelling annelid worm. The tubes is preserved as a flat carbonaceous organic or pyrite shadows left behind in shales, and as a relief imprints and casts in sandstones. Specimens have been found and documented in numerous Ediacaran localities of the White Sea area of Russia and possibly in Southeast China.
Shuhai Xiao is a paleontologist and professor of geobiology at Virginia Tech, Blacksburg, Virginia, U.S.A.
