Velumbrella Temporal range: | |
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Scientific classification ![]() | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Clade: | † Cambroernida |
Class: | † Eldonioidea |
Family: | † Rotadiscidae (?) |
Genus: | † Velumbrella Stasińska 1960 |
Type species | |
V. czarnockii Stasińska 1960 |
Velumbrella is an eldonioid [1] known from the Early to Middle Cambrian of Poland. [2] The fossils depict a scleritosed disk with a U-shaped gut. [3]
Velumbrella was originally thought to be related to the hydrozoan order Trachylenida, [4] or possibly to Ediacaria or Beltanella which were considered to be Cambrian jellyfish. [5] Upon erecting the class Eldonioidea, Dzik assigned Vellumbrella to Eldoniidae rather than Rotadiscidae on account of its radial ribs. [6]
Several authors (including Dzik) later noted the similarity between Velumbrella cznarnockii and Pararotadiscus guizhouensis (which was initially described as Rotadiscus guizhouensis). [7] [8] A more recent review tenatively placed Velumbrella in the Rotadiscidae (along with the more confidently-assigned Pararotadiscus), [1] noting that the rotadiscids are distinguished from other eldonioid families by concentric ornamentations on the dorsal surface. [9]
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.
Anomalocarididae is an extinct family of Cambrian radiodonts, a group of stem-group arthropods.
The small shelly fauna, small shelly fossils (SSF), or early skeletal fossils (ESF) are mineralized fossils, many only a few millimetres long, with a nearly continuous record from the latest stages of the Ediacaran to the end of the Early Cambrian Period. They are very diverse, and there is no formal definition of "small shelly fauna" or "small shelly fossils". Almost all are from earlier rocks than more familiar fossils such as trilobites. Since most SSFs were preserved by being covered quickly with phosphate and this method of preservation is mainly limited to the late Ediacaran and early Cambrian periods, the animals that made them may actually have arisen earlier and persisted after this time span.
Occacaris is an extinct nektonic predatory arthropod from the Lower Cambrian Maotianshan shale Lagerstätte, known from three species. It bears a superficial resemblance to the Cambrian arthropod, Canadaspis, though, was much smaller, and had a pair of "great appendages", with which it may have grasped prey. It was originally considered to belong to Megacheira, however it is questioned in later study.
The palaeoscolecids are a group of extinct ecdysozoan worms resembling armoured priapulids. They are known from the Lower Cambrian to the lower Ludfordian ; 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.
Eldonia is an extinct soft-bodied cambroernid best known from the Fossil Ridge outcrops of the Burgess Shale, particularly in the 'Great Eldonia layer' in the Walcott Quarry. In addition to over 550 specimens collected by Walcott, 224 specimens of Eldonia are known from the Greater Phyllopod bed, where they comprise 0.43% of the community. Species also occur in the Chengjiang biota, Siberia, and in Upper Ordovician strata of Morocco.
Eldonioids are an extinct clade of disc-shaped cambroernids, the Eldonioidea, which lived in the early to middle Paleozoic. The terms "eldonioid" and "eldoniid" have been used somewhat informally and interchangeably, but technically refer to members of the class Eldonioidea and the family Eldoniidae, respectively. The lifestyle of eldonioids is still an unresolved question; some authors reconstruct eldonioids as free-floating planktonic predators similar to jellyfish, while others argue that they were passive detritivores, embedded within the seabed for much of their life.
Stellostomites is a discoidal animal known from the Cambrian Chengjiang biota. It is classified with the eldoniids, and considered a junior synonym of Eldonia by some authors.
Paropsonema is an eldonioid known from the Devonian of upstate New York and the Silurian of southern Australia. It is the latest-surviving known member of the Eldonioidea and Cambroernida.
Rotadiscus is a genus of discoidal animal known from the Cambrian Chengjiang biota and classified with the eldonioids.
Ellipsocephalus Zenker, 1833, is a genus of blind Cambrian trilobite, comprising benthic species inhabiting deep, poorly lit or aphotic habitats. E. hoffi is a common trilobite mainly from central Europe.
Mongolitubulus is a form genus encapsulating a range of ornamented conical small shelly fossils of the Cambrian period. It is potentially synonymous with Rushtonites, Tubuterium and certain species of Rhombocorniculum, and owing to the similarity of the genera, they are all dealt with herein. Organisms that bore Mongolitubulus-like projections include trilobites, bradoriid arthropods and hallucigeniid lobopodians.
The Cambroernida are a clade of unusual Paleozoic animals with coiled bodies and filamentous tentacles. They include a number of early to middle Paleozoic genera noted as "bizarre" or "orphan" taxa, meaning that their affinities with other animals, living or extinct, have long been uncertain. While initially defined as an "informal stem group," later work with better-preserved fossils has strengthened the argument for Cambroernida as a monophyletic clade.
Paleontology or palaeontology is the study of prehistoric life forms on Earth through the examination of plant and animal fossils. This includes the study of body fossils, tracks (ichnites), burrows, cast-off parts, fossilised feces (coprolites), palynomorphs and chemical residues. Because humans have encountered fossils for millennia, paleontology has a long history both before and after becoming formalized as a science. This article records significant discoveries and events related to paleontology that occurred or were published in the year 2014.
Paleontology or palaeontology is the study of prehistoric life forms on Earth through the examination of plant and animal fossils. This includes the study of body fossils, tracks (ichnites), burrows, cast-off parts, fossilised feces (coprolites), palynomorphs and chemical residues. Because humans have encountered fossils for millennia, paleontology has a long history both before and after becoming formalized as a science. This article records significant discoveries and events related to paleontology that occurred or were published in the year 2015.
Jerzy Dzik is a Polish paleontologist.
The camenellans, consisting of the genera Camenalla, Dailyatia, Kennardia, Kelanella, Wufengella and Lapworthella, are a group of Tommotiid invertebrates from the Cambrian period, reconstructed as sister to all others. They are primarily known from isolated sclerites, but are believed to have a scleritomous, Halkieria-like construction. This was confirmed by the discovery of Wufengella, known from articulated remains, which showed camenellans to be mobile, worm-like animals.
Zhenghecaris is an extinct genus of enigmatic arthropods from the Lower Cambrian Maotianshan Shales, tentatively classified as a hurdiid (peytoiid) radiodont, and originally as a thylacocephalan. The genus contains a single species, Zhenghecaris shankouensis, known from several specimens mostly preserving the carapace and eyes. These specimens measure roughly 15 cm (5.9 in) in width, making it one of the largest thylacocephalans, behind Ostenocaris, Dollocaris and Ainiktozoon, as well as the earliest since all other thylacocephalans are Ordovician or younger. Better preserved fossils show that it was more similar to the domed sclerites of radiodonts such as Cambroraster, with two lateral spine processes on either side of the carapace, the eyes apparently fitting into the posterior notches. Additional isolated sclerites from the Chengjiang have been described as the lateral sclerites of Zhenghecaris due to their broad similarity to the P-elements of hurdiids (peytoiids), and because of their similar construction, ornamentation, and possession of two-pronged lateral spine processes. It has also been classified conservatively as Arthropoda incertae sedis, as the fragmentary remains cannot confidently be classified further due to the lack of associated appendages of trunk elements.