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Eucoelomata
Ecdysozoa () is a group of protostome animals, including Arthropoda (insects, chelicerates (including arachnids), crustaceans, and myriapods), Nematoda, and several smaller phyla. The grouping of these animal phyla into a single clade was first proposed by Eernisse ''et al.'' (1992) based on a phylogenetic analysis of 141 morphological characters of ultrastructural and embryological phenotypes. This clade, that is, a group consisting of a common ancestor and all its descendants, was formally named by Aguinaldo ''et al.'' in 1997, based mainly on phylogenetic trees constructed using 18S ribosomal RNA genes. A large study in 2008 by Dunn ''et al.'' strongly supported the monophyly of Ecdysozoa. The group Ecdysozoa is supported by many morphological characters, including growth by ecdysis, with moulting of the cuticle – without mitosis in the epidermis – under control of the prohormone ecdysone, and internal fertilization. The group was initially contested by a significant min ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ediacaran
The Ediacaran ( ) is a geological period of the Neoproterozoic geologic era, Era that spans 96 million years from the end of the Cryogenian Period at 635 Million years ago, Mya to the beginning of the Cambrian Period at 538.8 Mya. It is the last period of the Proterozoic geologic eon, Eon as well as the last of the so-called "Precambrian supereon", before the beginning of the subsequent Cambrian Period marks the start of the Phanerozoic Eon, where recognizable fossil evidence of life becomes common. The Ediacaran Period is named after the Ediacara Hills of South Australia, where trace fossils of a diverse community of previously unrecognized lifeforms (later named the Ediacaran biota) were first discovered by geologist Reg Sprigg in 1946. Its status as an official geological period was ratified in 2004 by the International Union of Geological Sciences (IUGS), making it the first new geological period declared in 120 years. Although the period took namesake from the Ediacara Hills ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uncus Dzaugisi
''Uncus dzaugisi'' was a species of animal which lived approximately 560 to 550million years ago during the late Ediacaran in what is now Southern Australia. Its smooth cylindrical shape, with one end being wider than the other, suggests that it was a member of the clade Ecdysozoa (a group containing arthropods, nematodes and tardigrades, amongst others). This makes it the oldest ecdysozoan known so far, as well as one of the oldest known bilaterians. It is currently the only member of the genus ''Uncus''. Discovery and name The systematic excavation that led to the discovery of ''Uncus'' began in 2018 in the Ediacara Member, a Stratigraphic unit, rock unit of the Rawnsley Quartzite within the Nilpena Ediacara National Park, South Australia, which is known for its well preserved Ediacaran biota, Ediacaran fossils. During the excavation, the team, led by Mary Droser, noted the presence of deep, hook-shaped indentations in the rock. At first, they were not looked into with much ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protostome
Protostomia () is the clade of animals once thought to be characterized by the formation of the organism's mouth before its anus during embryonic development. This nature has since been discovered to be extremely variable among Protostomia's members, although the reverse is typically true of its sister clade, Deuterostomia. Well-known examples of protostomes are arthropods, molluscs, annelids, flatworms and nematodes. They are also called schizocoelomates since schizocoely typically occurs in them. Together with the Deuterostomia and Xenacoelomorpha, these form the clade Bilateria, animals with bilateral symmetry, anteroposterior axis and three germ layers. Protostomy In animals at least as complex as earthworms, the first phase in gut development involves the embryo forming a dent on one side (the blastopore) which deepens to become its digestive tube (the archenteron). In the sister-clade, the deuterostomes (), the original dent becomes the anus while the gut eventua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saccus (genus) , being an anterior extension of the vinculum
{{Disambiguation ...
Saccus may refer to: * Saccus, Roman cognomen, see List of Roman cognomina * ''Saccus'', a genus of plants in the family Moraceae, synonym of ''Artocarpus'' * Saccus, in anatomy: ** Saccus endolymphaticus ** Saccus lacrimalis ** Saccus caecus caudodorsalis ** Saccus caecus caudoventralis ** Saccus conjunctivae ** Saccus cranialis ** Saccus dorsalis * Saccus, in entomology: ** Saccus (insect anatomy), an anatomical structure of male lepidoptera genitalia The study of the genitalia of Lepidoptera is important for Lepidoptera taxonomy in addition to development, anatomy and natural history. The genitalia are complex and provide the basis for species discrimination in most families and also in fami ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BMC Evolutionary Biology
''BMC Ecology and Evolution'' (since January 2021), previously ''BMC Evolutionary Biology'' (2001–2020), is a peer-reviewed open access scientific journal covering all fields of evolutionary biology, including phylogenetics and palaeontology. It was established in 2001 and is part of a series of BMC journals published by BioMed Central. It was an early journal to integrate with the Dryad Digital Repository to share supplementary data, and it also organises a yearly image competition to help capture the diversity of the planet's flora and fauna. Abstracting and indexing The journal is abstracted and indexed in: According to the ''Journal Citation Reports ''Journal Citation Reports'' (''JCR'') is an annual publication by Clarivate. It has been integrated with the Web of Science and is accessed from the Web of Science Core Collection. It provides information about academic journals in the natur ...'', the journal has a 2020 impact factor of 3.260. References E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acosmia
''Acosmia'' is an extinct genus of marine worm from the Cambrian aged Chengjiang biota of Yunnan, China. It is represented by a single rare species, ''Acosmia maotiania'', that reached 45 mm in length and 9 mm in width. It was likely a burrowing animal that fed by deposit feeding. While originally suggested to be a priapulid (penis worm), a 2020 study proposed to be a stem-group ecdysozoa Ecdysozoa () is a group of protostome animals, including Arthropoda (insects, chelicerates (including arachnids), crustaceans, and myriapods), Nematoda, and several smaller phylum (biology), phyla. The grouping of these animal phyla into a single ...n, due to lacking the radial pharygneal armature that characterises modern ecdysozoans, including priapulids. References Monotypic prehistoric protostome genera † Maotianshan shales fossils {{paleo-protostome-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nature (journal)
''Nature'' is a British weekly scientific journal founded and based in London, England. As a multidisciplinary publication, ''Nature'' features Peer review, peer-reviewed research from a variety of academic disciplines, mainly in science and technology. It has core editorial offices across the United States, continental Europe, and Asia under the international scientific publishing company Springer Nature. ''Nature'' was one of the world's most cited scientific journals by the Science Edition of the 2022 ''Journal Citation Reports'' (with an ascribed impact factor of 50.5), making it one of the world's most-read and most prestigious academic journals. , it claimed an online readership of about three million unique readers per month. Founded in the autumn of 1869, ''Nature'' was first circulated by Norman Lockyer and Alexander MacMillan (publisher), Alexander MacMillan as a public forum for scientific innovations. The mid-20th century facilitated an editorial expansion for the j ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saccorhytida
Saccorhytida is an extinct phylum of Cambrian animals possibly belonging to the superphylum Ecdysozoa. It contains three monotypic genera: its namesake '' Saccorhytus'', the dubious '' Clypecella'' and '' Beretella''. All three genera are found in the early Cambrian of China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after .... References † † Taxa described in 2017 Cambrian China Saccorhytida {{Paleo-protostome-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sialomorphidae
''Sialomorpha dominicana'', also known as the mold pig, is a panarthropod genus of uncertain affinities discovered in 30-million year old Dominican amber by George Poinar at Oregon State University and Diane R. Nelson at East Tennessee University. It was placed in a new genus and family (Sialomorphidae) unto itself, and appears to represent a new phylum. ''S. dominicana'' shares some resemblance to tardigrades and mite Mites are small arachnids (eight-legged arthropods) of two large orders, the Acariformes and the Parasitiformes, which were historically grouped together in the subclass Acari. However, most recent genetic analyses do not recover the two as eac ...s. It is about 100 μm long and grew by molting its exoskeleton. It was probably an omnivore, feeding on minute invertebrates and fungi, including mold. References {{Taxonbar, from1=Q70464160, from2=Q70464040, from3=Q70464216 Cenozoic invertebrates Monotypic prehistoric protostome genera Fossil taxa de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tardigrada
Tardigrades (), known colloquially as water bears or moss piglets, are a phylum of eight-legged Segmentation (biology), segmented micro-animals. They were first described by the German zoologist Johann August Ephraim Goeze in 1773, who called them . In 1776, the Italian biologist Lazzaro Spallanzani named them Tardigrada, which means 'slow walkers'. They live in diverse regions of Earth's biospheremountaintops, the deep sea, tropical rainforests, and the Antarctic. Tardigrades are among the most resilient animals known, with individual species able to survive extreme conditions – such as exposure to extreme temperatures, extreme pressures (both high and low), air deprivation, radiation, dehydration, and starvation – that would quickly kill most other forms of life. Tardigrades have survived exposure to outer space. There are about 1,500 known species in the phylum Tardigrada, a part of the superphylum Ecdysozoa. The earliest known fossil is from the Cambrian, some 500 m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthropoda
Arthropods ( ) are invertebrates in the phylum Arthropoda. They possess an exoskeleton with a cuticle made of chitin, often mineralised with calcium carbonate, a body with differentiated ( metameric) segments, and paired jointed appendages. In order to keep growing, they must go through stages of moulting, a process by which they shed their exoskeleton to reveal a new one. They form an extremely diverse group of up to ten million species. Haemolymph is the analogue of blood for most arthropods. An arthropod has an open circulatory system, with a body cavity called a haemocoel through which haemolymph circulates to the interior organs. Like their exteriors, the internal organs of arthropods are generally built of repeated segments. They have ladder-like nervous systems, with paired ventral nerve cords running through all segments and forming paired ganglia in each segment. Their heads are formed by fusion of varying numbers of segments, and their brains are formed by fu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
