|
Latromirus
''Parioscorpio'' is an extinct genus of arthropod containing the species ''P. venator'' known from the Silurian-aged Waukesha Biota of the Brandon Bridge Formation near Waukesha, Wisconsin. Taxonomy The fossils were originally discovered in 1985, tentatively identified as a branchiopod or remipede crustacean but were neglected for decades. In 2016, some of the fossils now assigned to ''Parioscorpio'' were given the name ''Latromirus'' and were assigned to an extinct group of early Paleozoic arthropods known as cheloniellids in a Ph.D dissertation, but the name was never published in a peer-reviewed journal and is therefore not valid in accordance with the International Code of Zoological Nomenclature. Upon initial publication in 2020, ''Parioscorpio'' was considered the world's oldest and most primitive known scorpion, older than '' Dolichophonus'' from Scotland by several million years. In 2021, the fossils were reanalysed, and ''Parioscorpio'' was found not to be a scorpion, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cheloniellid
Cheloniellida is a taxon (usually referred to as an order) of extinct Paleozoic arthropods. As of 2018,Wendruff, Andrew James, et al. "New cheloniellid arthropod with large raptorial appendages from the Silurian of Wisconsin, USA." BioRxiv (2018): 407379/ref> 7 monotypic genera of cheloniellids had been formally described, whose fossils are found in marine strata ranging from Ordovician to Devonian in age. Cheloniellida has a controversial phylogenetic position, with previous studies associated it as either a member or relative of various fossil and extant arthropod taxa. It was later accepted as a member of Vicissicaudata within Artiopoda. Morphology The flattened, ovoid body of cheloniellid comprises an eye-bearing cephalon (head) and segmented trunk region, dorsally divided by a series of tergites (dorsal exoskeleton). The cephalon could be divided into procephalon and gnathocephalon. Compared to other members of Artiopoda, the head shield (dorsal exoskeleton of cephalon) of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Waukesha Biota
The Waukesha Biota (also known as Waukesha Lagerstätte, Brandon Bridge Lagerstätte, or Brandon Bridge fauna) refers to a Konservat-Lagerstätte ( a fossil site that preserves soft bodied remains) of Early Silurian ( Telychian to Sheinwoodian) age found within the Brandon Bridge Formation in Waukesha County and Franklin, Milwaukee County, Wisconsin. It is known for the exceptional preservation of its diverse, soft-bodied and lightly skeletonized taxa, including many major taxa found nowhere else in strata of similar age. The sites discovery was announced in 1985, thus leading to a wide plethora of discoveries being made. This biota is one of the few well studied lagerstättes from the Silurian, making it very important in our understanding of Silurian faunas. Some of the taxa found here are not easily classified into known animal groups, showing that there is a great amount of studying that needs to be done on this site. Other taxa that are normally common in other Silurian d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silurian
The Silurian ( ) is a geologic period and system spanning 24.6 million years from the end of the Ordovician Period, at million years ago (Mya), to the beginning of the Devonian Period, Mya. The Silurian is the shortest period of the Paleozoic Era. As with other geologic periods, the rock beds that define the period's start and end are well identified, but the exact dates are uncertain by a few million years. The base of the Silurian is set at a series of major Ordovician–Silurian extinction events when up to 60% of marine genera were wiped out. One important event in this period was the initial establishment of terrestrial life in what is known as the Silurian-Devonian Terrestrial Revolution: vascular plants emerged from more primitive land plants, dikaryan fungi started expanding and diversifying along with glomeromycotan fungi, and three groups of arthropods ( myriapods, arachnids and hexapods) became fully terrestrialized. A significant evolutionary milestone d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megacheira
Megacheira ("great hands") is an extinct class of predatory arthropods that possessed a pair of great appendages, hence the class name as well as the common name "great appendage arthropods". Their taxonomic position is controversial, with studies either considering them stem-group euarthropods, or stem-group chelicerates. Most of them were found in marine environments throughout the world from the lower to middle Cambrian. Megacheirans were important components of several faunas, including the Burgess, Wheeler and Maotianshan Shales Lagerstatten. Homology of great appendages The homology between megacheiran great appendages and cephalic appendages of other arthropods had been discussed for decades. There is controversy over whether they are homologous to both dinocaridid ( radiodonts and gilled lobopodians) frontal appendages, the frontalmost appendages of ''Isoxys'' and chelicerates' chelicerae. Based on neuroanatomical evidences, many studies support their homology ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypostome , the oral tip surrounded by tentacles in hydrozoan cnidarians
{{Set index article ...
In zoology, the hypostome can refer to structures in distinct animal groups: *Hypostome (trilobite), the ventral mouthpart plate in trilobites *Hypostome (tick), the barbed attachment structure associated with the mouthparts of parasitic arachnids *Hypostome (cnidarian) Hydrozoa (hydrozoans; ) are a taxonomic class of individually very small, predatory animals, some solitary and some colonial, most of which inhabit saline water. The colonies of the colonial species can be large, and in some cases the specialized ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pedipalp
Pedipalps (commonly shortened to palps or palpi) are the second pair of appendages of chelicerates – a group of arthropods including spiders, scorpions, horseshoe crabs, and sea spiders. The pedipalps are lateral to the chelicerae ("jaws") and anterior to the first pair of walking legs. Overview Pedipalps are composed of six segments or articles: the coxa, the trochanter, the femur, the short patella, the tibia, and the tarsus. In spiders, the coxae frequently have extensions called maxillae or gnathobases, which function as mouth parts with or without some contribution from the coxae of the anterior legs. The limbs themselves may be simple tactile organs outwardly resembling the legs, as in spiders, or chelate weapons ( pincers) of great size, as in scorpions. The pedipalps of Solifugae are covered in setae, but have not been studied in detail. Comparative studies of pedipalpal morphology may suggest that leg-like pedipalps are primitive in arachnids. At present, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chela (organ)
A chela ()also called a claw, nipper, or pinceris a pincer-like organ at the end of certain limbs of some arthropods. The name comes from Ancient Greek , through New Latin New Latin (also called Neo-Latin or Modern Latin) is the revival of Literary Latin used in original, scholarly, and scientific works since about 1500. Modern scholarly and technical nomenclature, such as in zoological and botanical taxonomy ... '. The plural form is chelae. Legs bearing a chela are called chelipeds. Another name is ''claw'' because most chelae are curved and have a sharp point like a claw. Chelae can be present at the tips of arthropod legs as well as their pedipalps. Chelae are distinct from spider chelicerae in that they do not contain venomous glands and cannot distribute venom. See also * Pincer (biology) * Pincer (tool) References Arthropod anatomy {{Arthropod-anatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
20211104 Parioscorpio Raptorial Appendages Mobility
111 may refer to: *111 (number) *111 BC * AD 111 *111 (emergency telephone number) *111 (Australian TV channel) * Swissair Flight 111 * ''111'' (Her Majesty & the Wolves album) * ''111'' (Željko Joksimović album) *NHS 111 *(111) a Miller index for the crystal face plane formed by cutting off the corner equally along each axis *111 (MBTA bus) *111 (New Jersey bus) * ''111'' (Pabllo Vittar album) See also *III (other) *List of highways numbered 111 *1/11 (other) 1/11 may refer to: *January 11 Events Pre-1600 * 532 – Nika riots in Constantinople: A quarrel between supporters of different chariot teams—the Blues and the Greens—in the Hippodrome escalates into violence. * 630 – Conqu ... * 11/1 (other) * Roentgenium, synthetic chemical element with atomic number 111 {{numberdis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basal (phylogenetics)
In phylogenetics, basal is the direction of the ''base'' (or root) of a rooted phylogenetic tree or cladogram. The term may be more strictly applied only to nodes adjacent to the root, or more loosely applied to nodes regarded as being close to the root. Note that extant taxa that lie on branches connecting directly to the root are not more closely related to the root than any other extant taxa. While there must always be two or more equally "basal" clades sprouting from the root of every cladogram, those clades may differ widely in taxonomic rank, species diversity, or both. If ''C'' is a basal clade within ''D'' that has the lowest rank of all basal clades within ''D'', ''C'' may be described as ''the'' basal taxon of that rank within ''D''. The concept of a 'key innovation' implies some degree of correlation between evolutionary innovation and diversification. However, such a correlation does not make a given case predicable, so ancestral characters should not be imputed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acheronauta Stimulapis
''Acheronauta'' is a genus of extinct vermiform arthropod that lived in the early Silurian (Telychian- Sheinwoodian stages) Waukesha biota fossil site in southeast Wisconsin. This arthropod was first discovered alongside the biota in 1985, but wasn't fully described until October 2022. This creature was recognized and described as a possible early mandibulate (the grouping of arthropods including crustaceans and hexapods). This description is very important as much of the fauna of the biota remain undescribed, and it's discovery has allowed for paleontologists to get a better grasp of the diversity of the arthropod fauna at the site. Multiple phylogenetic analyses were preformed, and it seems that this arthropod forms a previously undiscovered clade with the Devonian stem-arthropod ''Captopodus'', and the somewhat enigmatic group Thylacocephala. ''Acheronauta'' has been assessed as a possible basal mandibulate, which are distinguished from other arthropods due to the presence ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stem-group
In phylogenetics, the crown group or crown assemblage is a collection of species composed of the living representatives of the collection, the most recent common ancestor of the collection, and all descendants of the most recent common ancestor. It is thus a way of defining a clade, a group consisting of a species and all its extant or extinct descendants. For example, Neornithes (birds) can be defined as a crown group, which includes the most recent common ancestor of all modern birds, and all of its extant or extinct descendants. The concept was developed by Willi Hennig, the formulator of phylogenetic systematics, as a way of classifying living organisms relative to their extinct relatives in his "Die Stammesgeschichte der Insekten", and the "crown" and "stem" group terminology was coined by R. P. S. Jefferies in 1979. Though formulated in the 1970s, the term was not commonly used until its reintroduction in 2000 by Graham Budd and Sören Jensen. Contents of the crown ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aglaspidida
Aglaspidida is an extinct order of aquatic arthropods that were once regarded as primitive chelicerates. However, anatomical comparisons demonstrate that the aglaspidids cannot be accommodated within the chelicerates, and that they lie instead within the Artiopoda, thus placing them closer to the trilobites. Aglaspidida contains the subgroups Aglaspididae and Tremaglaspididae, which are distinguished by the presence of acute/spinose genal angles and a long spiniform tailspine in the Aglaspididae. Aglaspidid fossils are found in North America (upper Mississippi valley, Missouri and Utah), Europe, Australia, and China. Certain other artiopods are believed to be closely related to the aglaspidids, including the order Strabopida, which includes the genera ''Strabops'', '' Paleomerus'', ''Parapaleomerus'', and possibly ''Khankaspis''. List of genera *'' Aglaspella'' *''Aglaspis'' *'' Aglaspoides'' *'' Australaglaspis'' *'' Beckwithia'' *'' Chlupacaris'' *'' Chraspedops'' *'' Cyc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
