99-717: Hyla triseriata Helocaetes triseriatus Chorophilus triseriatus Chorophilus nigritus triseriatus The western chorus frog ( Pseudacris triseriata ), also known as striped chorus frog , or midland chorus frog is a species of frog found in Canada and the United States . Western chorus frogs are small 40 mm (1.6 in), smooth skinned, and greenish-grey, reddish, olive, or brown in color. Differences in color can occur locally and should not be confused for range-specific populations. Typically, these frogs have three dark-brown or grey stripes which extend down
198-425: A cephalothorax (with no separate head) or prosoma, and an opisthosoma or abdomen. Segmentation has almost entirely been lost and the prosoma and opisthosoma are fused, only the positioning of the limbs indicating the location of the segments. At the front of the body is the gnathosoma or capitulum. This is not a head and does not contain the eyes or the brain, but is a retractable feeding apparatus consisting of
297-423: A mutation–selection balance . It is predicted that a viral quasispecies at a low but evolutionarily neutral and highly connected (that is, flat) region in the fitness landscape will outcompete a quasispecies located at a higher but narrower fitness peak in which the surrounding mutants are unfit, "the quasispecies effect" or the "survival of the flattest". There is no suggestion that a viral quasispecies resembles
396-408: A prion disease of sheep. The mite Varroa destructor is a serious pest of honey bees , contributing to colony collapse disorder in commercial hives . This organism is an obligate external parasite, able to reproduce only in bee colonies. It directly weakens its host by sucking up the bee's fat, and can spread RNA viruses including deformed wing virus . Heavy infestation causes the death of
495-670: A subspecies of the southern chorus frog, P. nigrita , but was reclassified as its own species with four subspecies: P. t. triseriata , P. t. kalmi , P. t. maculata , and P. t. feriarum . These have since been granted species status, meaning P. triseriata as described here has no subspecies. This chorus frog has a huge distribution, from Canada to the Gulf of Mexico , and New Jersey to central Arizona . The frogs lives from near sea level to about 12,000 ft (3,700 m) above sea level, and are capable of surviving temperatures as low as –8 °C. Western chorus frogs live in
594-400: A "classical" method of determining species, such as with Linnaeus, early in evolutionary theory. However, different phenotypes are not necessarily different species (e.g. a four-winged Drosophila born to a two-winged mother is not a different species). Species named in this manner are called morphospecies . In the 1970s, Robert R. Sokal , Theodore J. Crovello and Peter Sneath proposed
693-424: A 'smallest clade' idea" (a phylogenetic species concept). Mishler and Wilkins and others concur with this approach, even though this would raise difficulties in biological nomenclature. Wilkins cited the ichthyologist Charles Tate Regan 's early 20th century remark that "a species is whatever a suitably qualified biologist chooses to call a species". Wilkins noted that the philosopher Philip Kitcher called this
792-583: A colony, generally over the winter. Since 2006, more than 10 million beehives have been lost. Various mites prey on other invertebrates and can be used to control their populations. Phytoseiidae , especially members of Amblyseius , Metaseiulus , and Phytoseiulus , are used to control pests such as spider mites. Among the Laelapidae , Gaeolaelaps aculeifer and Stratiolaelaps scimitus are used to control fungus gnats , poultry red mites and various soil pests. Mites were first observed under
891-428: A connected series of neighbouring populations, each of which can sexually interbreed with adjacent related populations, but for which there exist at least two "end" populations in the series, which are too distantly related to interbreed, though there is a potential gene flow between each "linked" population. Such non-breeding, though genetically connected, "end" populations may co-exist in the same region thus closing
990-432: A different species from its ancestors. Viruses have enormous populations, are doubtfully living since they consist of little more than a string of DNA or RNA in a protein coat, and mutate rapidly. All of these factors make conventional species concepts largely inapplicable. A viral quasispecies is a group of genotypes related by similar mutations, competing within a highly mutagenic environment, and hence governed by
1089-522: A few phylogenomic studies have found strong support for monophyly of Acari and a sister relationship between Acariformes and Parasitiformes, although this finding has been questioned, with other studies suggesting that this likely represents a long branch attraction artefact. Mites are tiny members of the class Arachnida ; most are in the size range 250 to 750 μm (0.01 to 0.03 in) but some are larger and some are no bigger than 100 μm (0.004 in) as adults. The body plan has two regions ,
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#17327932498871188-508: A genetic boundary suitable for defining a species concept is present. DNA barcoding has been proposed as a way to distinguish species suitable even for non-specialists to use. One of the barcodes is a region of mitochondrial DNA within the gene for cytochrome c oxidase . A database, Barcode of Life Data System , contains DNA barcode sequences from over 190,000 species. However, scientists such as Rob DeSalle have expressed concern that classical taxonomy and DNA barcoding, which they consider
1287-465: A lineage should be divided into multiple chronospecies , or when populations have diverged to have enough distinct character states to be described as cladistic species. Species and higher taxa were seen from the time of Aristotle until the 18th century as categories that could be arranged in a hierarchy, the great chain of being . In the 19th century, biologists grasped that species could evolve given sufficient time. Charles Darwin 's 1859 book On
1386-439: A million or more species as yet undescribed. The tropical species Archegozetes longisetosus is one of the strongest animals in the world, relative to its mass (100 μg): It lifts up to 1,182 times its own weight, over five times more than would be expected of such a minute animal. A mite also holds a speed record: for its length, Paratarsotomus macropalpis is the fastest animal on Earth. The mites living in soil consist of
1485-492: A misnomer, need to be reconciled, as they delimit species differently. Genetic introgression mediated by endosymbionts and other vectors can further make barcodes ineffective in the identification of species. A phylogenetic or cladistic species is "the smallest aggregation of populations (sexual) or lineages (asexual) diagnosable by a unique combination of character states in comparable individuals (semaphoronts)". The empirical basis – observed character states – provides
1584-765: A network of sinuses and most mites lacks a heart, movement of fluid being driven by the contraction of body muscles. But ticks, and some of the larger species of mites, have a dorsal, longitudinal heart. Gas exchange is carried out across the body surface, but many species additionally have between one and four pairs of tracheae . The excretory system includes a nephridium and one or two pairs of Malpighian tubules . Several families of mites, such as Tetranychidae, Eriophyidae, Camerobiidae, Cunaxidae, Trombidiidae, Trombiculidae, Erythraeidae and Bdellidae have silk glands used to produce silk for various purposes. Additionally, water mites (Hydrachnidia) produce long thin threads that may be silk. The sexes are separate in mites; males have
1683-418: A pair of testes in the mid-region of the body, each connected to the gonopore by a vas deferens , and in some species there is a chitinous penis ; females have a single ovary connected to the gonopore by an oviduct , as well as a seminal receptacle for the storage of sperm . In most mites, sperm is transferred to the female indirectly; the male either deposits a spermatophore on a surface from which it
1782-449: A particular species, including which genus (and higher taxa) it is placed in, is a hypothesis about the evolutionary relationships and distinguishability of that group of organisms. As further information comes to hand, the hypothesis may be corroborated or refuted. Sometimes, especially in the past when communication was more difficult, taxonomists working in isolation have given two distinct names to individual organisms later identified as
1881-400: A perfect model of life, it is still a useful tool to scientists and conservationists for studying life on Earth, regardless of the theoretical difficulties. If species were fixed and clearly distinct from one another, there would be no problem, but evolutionary processes cause species to change. This obliges taxonomists to decide, for example, when enough change has occurred to declare that
1980-448: A range of taxa. Oribatida and Prostigmata are more numerous in soil than Mesostigmata, and have more soil-dwelling species. When soil is affected by an ecological disturbance such as agriculture, most mites (Astigmata, Mesostigmata and Prostigmata) recolonise it within a few months, whereas Oribatida take multiple years. Many mites are parasitic on plants and animals. One family of mites, Pyroglyphidae , or nest mites, live primarily in
2079-400: A short way of saying that something applies to many species within a genus, but not to all. If scientists mean that something applies to all species within a genus, they use the genus name without the specific name or epithet. The names of genera and species are usually printed in italics . However, abbreviations such as "sp." should not be italicised. When a species' identity is not clear,
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#17327932498872178-542: A small scale, walking is used to access other suitable locations in the immediate vicinity. Some species mount to a high point and adopt a dispersal posture and get carried away by the wind, while others waft a thread of silk aloft to balloon to a new position. Parasitic mites use their hosts to disperse, and spread from host to host by direct contact. Another strategy is phoresy ; the mite, often equipped with suitable claspers or suckers, grips onto an insect or other animal, and gets transported to another place. A phoretic mite
2277-513: A special call to attract several potential mates to breeding sites. The western chorus frog call can be heard from half a mile away. The call is a very distinct "cree-ee-ee—eeek", but can be confused with the upland chorus frog. Calling can occur for 0.5–2.0 seconds and can occur 18–20 times in a minute. The higher the temperature, the more frequent calls occur in a minute, (30–90 calls per minute). The western chorus frog relies heavily on secrecy to keep themselves safe from predators. Any disturbances to
2376-404: A specialist may use "cf." before the epithet to indicate that confirmation is required. The abbreviations "nr." (near) or "aff." (affine) may be used when the identity is unclear but when the species appears to be similar to the species mentioned after. With the rise of online databases, codes have been devised to provide identifiers for species that are already defined, including: The naming of
2475-523: A species as groups of actually or potentially interbreeding natural populations, which are reproductively isolated from other such groups. It has been argued that this definition is a natural consequence of the effect of sexual reproduction on the dynamics of natural selection. Mayr's use of the adjective "potentially" has been a point of debate; some interpretations exclude unusual or artificial matings that occur only in captivity, or that involve animals capable of mating but that do not normally do so in
2574-400: A species as determined by a taxonomist. A typological species is a group of organisms in which individuals conform to certain fixed properties (a type), so that even pre-literate people often recognise the same taxon as do modern taxonomists. The clusters of variations or phenotypes within specimens (such as longer or shorter tails) would differentiate the species. This method was used as
2673-491: A species. All species definitions assume that an organism acquires its genes from one or two parents very like the "daughter" organism, but that is not what happens in HGT. There is strong evidence of HGT between very dissimilar groups of prokaryotes , and at least occasionally between dissimilar groups of eukaryotes , including some crustaceans and echinoderms . The evolutionary biologist James Mallet concludes that there
2772-685: A species. Generally the term includes the unknown element of a distinct act of creation. Many authors have argued that a simple textbook definition, following Mayr's concept, works well for most multi-celled organisms , but breaks down in several situations: Species identification is made difficult by discordance between molecular and morphological investigations; these can be categorised as two types: (i) one morphology, multiple lineages (e.g. morphological convergence , cryptic species ) and (ii) one lineage, multiple morphologies (e.g. phenotypic plasticity , multiple life-cycle stages). In addition, horizontal gene transfer (HGT) makes it difficult to define
2871-528: A taxonomic decision at the discretion of cognizant specialists, is not governed by the Codes of Zoological or Botanical Nomenclature, in contrast to the PhyloCode , and contrary to what is done in several other fields, in which the definitions of technical terms, like geochronological units and geopolitical entities, are explicitly delimited. The nomenclatural codes that guide the naming of species, including
2970-517: A traditional biological species. The International Committee on Taxonomy of Viruses has since 1962 developed a universal taxonomic scheme for viruses; this has stabilised viral taxonomy. Most modern textbooks make use of Ernst Mayr 's 1942 definition, known as the Biological Species Concept as a basis for further discussion on the definition of species. It is also called a reproductive or isolation concept. This defines
3069-447: A variation on the morphological species concept, a phenetic species, defined as a set of organisms with a similar phenotype to each other, but a different phenotype from other sets of organisms. It differs from the morphological species concept in including a numerical measure of distance or similarity to cluster entities based on multivariate comparisons of a reasonably large number of phenotypic traits. A mate-recognition species
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3168-705: A variety of different habitats , but areas of more permanent water increase the risk of predation on eggs and/or tadpoles. To compensate for this, chorus frogs stick to mostly ephemeral freshwater areas, such as marshes, river swamps, meadows, grassy pools, and other open areas found in mountains and prairies. The western chorus frog remains close to these ephemeral aquatic habitats, since they provide excellent mating, breeding, and hibernation grounds. Since these areas tend to dry out, these frogs can be, but are less commonly, found in fallowed agricultural fields, damp woodlands, roadside ditches, and wooded swamps. Both males and sometimes females call in large choruses . Males use
3267-515: A variety of reasons. Viruses are a special case, driven by a balance of mutation and selection , and can be treated as quasispecies . Biologists and taxonomists have made many attempts to define species, beginning from morphology and moving towards genetics . Early taxonomists such as Linnaeus had no option but to describe what they saw: this was later formalised as the typological or morphological species concept. Ernst Mayr emphasised reproductive isolation, but this, like other species concepts,
3366-438: Is "an entity composed of organisms which maintains its identity from other such entities through time and over space, and which has its own independent evolutionary fate and historical tendencies". This differs from the biological species concept in embodying persistence over time. Wiley and Mayden stated that they see the evolutionary species concept as "identical" to Willi Hennig 's species-as-lineages concept, and asserted that
3465-400: Is a group of sexually reproducing organisms that recognise one another as potential mates. Expanding on this to allow for post-mating isolation, a cohesion species is the most inclusive population of individuals having the potential for phenotypic cohesion through intrinsic cohesion mechanisms; no matter whether populations can hybridise successfully, they are still distinct cohesion species if
3564-458: Is a set of organisms adapted to a particular set of resources, called a niche, in the environment. According to this concept, populations form the discrete phenetic clusters that we recognise as species because the ecological and evolutionary processes controlling how resources are divided up tend to produce those clusters. A genetic species as defined by Robert Baker and Robert Bradley is a set of genetically isolated interbreeding populations. This
3663-414: Is called speciation . Charles Darwin was the first to describe the role of natural selection in speciation in his 1859 book The Origin of Species . Speciation depends on a measure of reproductive isolation , a reduced gene flow. This occurs most easily in allopatric speciation, where populations are separated geographically and can diverge gradually as mutations accumulate. Reproductive isolation
3762-412: Is called the specific name or the specific epithet (in botanical nomenclature , also sometimes in zoological nomenclature ). For example, Boa constrictor is one of the species of the genus Boa , with constrictor being the species' epithet. While the definitions given above may seem adequate at first glance, when looked at more closely they represent problematic species concepts. For example,
3861-403: Is described formally, in a publication that assigns it a unique scientific name. The description typically provides means for identifying the new species, which may not be based solely on morphology (see cryptic species ), differentiating it from other previously described and related or confusable species and provides a validly published name (in botany) or an available name (in zoology) when
3960-671: Is further weakened by the existence of microspecies , groups of organisms, including many plants, with very little genetic variability, usually forming species aggregates . For example, the dandelion Taraxacum officinale and the blackberry Rubus fruticosus are aggregates with many microspecies—perhaps 400 in the case of the blackberry and over 200 in the dandelion, complicated by hybridisation , apomixis and polyploidy , making gene flow between populations difficult to determine, and their taxonomy debatable. Species complexes occur in insects such as Heliconius butterflies, vertebrates such as Hypsiboas treefrogs, and fungi such as
4059-726: Is hard or even impossible to test. Later biologists have tried to refine Mayr's definition with the recognition and cohesion concepts, among others. Many of the concepts are quite similar or overlap, so they are not easy to count: the biologist R. L. Mayden recorded about 24 concepts, and the philosopher of science John Wilkins counted 26. Wilkins further grouped the species concepts into seven basic kinds of concepts: (1) agamospecies for asexual organisms (2) biospecies for reproductively isolated sexual organisms (3) ecospecies based on ecological niches (4) evolutionary species based on lineage (5) genetic species based on gene pool (6) morphospecies based on form or phenotype and (7) taxonomic species,
Western chorus frog - Misplaced Pages Continue
4158-440: Is just a hitch-hiker and does not feed during the time it is carried by its temporary host. These travelling mites are mostly species that reproduce rapidly and are quick to colonise new habitats. Mites are tiny and apart from those that are of economic concern to humans, little studied. The majority are beneficial, living in the soil or aqueous environments and assisting in the decomposition of decaying organic material, as part of
4257-491: Is located on the ventral surface between the fourth pair of legs. Some species have one to five median or lateral eyes but many species are blind, and slit and pit sense organs are common. Both body and limbs bear setae (bristles) which may be simple, flattened, club-shaped or sensory. Mites are usually some shade of brown, but some species are red, orange, black or green, or some combination of these colours. Many mites have stigmata (openings used in respiration). In some mites,
4356-403: Is no easy way to tell whether related geographic or temporal forms belong to the same or different species. Species gaps can be verified only locally and at a point of time. One is forced to admit that Darwin's insight is correct: any local reality or integrity of species is greatly reduced over large geographic ranges and time periods. The botanist Brent Mishler argued that the species concept
4455-478: Is not valid, notably because gene flux decreases gradually rather than in discrete steps, which hampers objective delimitation of species. Indeed, complex and unstable patterns of gene flux have been observed in cichlid teleosts of the East African Great Lakes . Wilkins argued that "if we were being true to evolution and the consequent phylogenetic approach to taxa, we should replace it with
4554-464: Is picked up by the female, or he uses his chelicerae or third pair of legs to insert it into the female's gonopore. In some of the Acariformes , insemination is direct using the male's penis. The spermatophora in all mites are aflagellate. The eggs are laid in the substrate , or wherever the mite happens to live. They take up to six weeks to hatch, according to species, with the next stage being
4653-586: Is similar to Mayr's Biological Species Concept, but stresses genetic rather than reproductive isolation. In the 21st century, a genetic species could be established by comparing DNA sequences. Earlier, other methods were available, such as comparing karyotypes (sets of chromosomes ) and allozymes ( enzyme variants). An evolutionarily significant unit (ESU) or "wildlife species" is a population of organisms considered distinct for purposes of conservation. In palaeontology , with only comparative anatomy (morphology) and histology from fossils as evidence,
4752-469: Is sometimes an important source of genetic variation. Viruses can transfer genes between species. Bacteria can exchange plasmids with bacteria of other species, including some apparently distantly related ones in different phylogenetic domains , making analysis of their relationships difficult, and weakening the concept of a bacterial species. Mites Mites are small arachnids (eight-legged arthropods ). Mites span two large orders of arachnids,
4851-594: Is threatened by hybridisation, but this can be selected against once a pair of populations have incompatible alleles of the same gene, as described in the Bateson–Dobzhansky–Muller model . A different mechanism, phyletic speciation, involves one lineage gradually changing over time into a new and distinct form (a chronospecies ), without increasing the number of resultant species. Horizontal gene transfer between organisms of different species, either through hybridisation , antigenic shift , or reassortment ,
4950-735: 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 each other's closest relative within Arachnida, rendering the group non- monophyletic . Most mites are tiny, less than 1 mm (0.04 in) in length, and have a simple, unsegmented body plan. The small size of most species makes them easily overlooked; some species live in water, many live in soil as decomposers , others live on plants, sometimes creating galls , while others are predators or parasites . This last type includes
5049-530: The ICZN for animals and the ICN for plants, do not make rules for defining the boundaries of the species. Research can change the boundaries, also known as circumscription, based on new evidence. Species may then need to be distinguished by the boundary definitions used, and in such cases the names may be qualified with sensu stricto ("in the narrow sense") to denote usage in the exact meaning given by an author such as
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#17327932498875148-822: The IUCN list, the US Federal List has the species labeled as no special status. In Canada, the western chorus frog is listed as threatened in the Great Lakes/St. Lawrence - Canadian Shield under the Species at Risk Act (SARA) . The western chorus frog is currently the subject of a legal dispute over compensation between a landowner and the Government of Canada. The western chorus frog plays an important role as an indicator species . Deformities, reduction in reproductive success, or changes in morphology in either
5247-527: The Parasitiformes (sometimes known as Anactinotrichida). Recent genetic research has suggested that Acari is polyphyletic (of multiple origins). A study using molecular data from the mitochondria and nucleus recovered Acariformes as sister to the Solifugae (camel spiders) and Parasitiformes as sister to the Pseudoscorpionida , with other arachnid orders separating these two groupings on
5346-559: The Rhynie Chert , Scotland, which dates to the early Devonian , around 410 million years ago while the earliest fossils of Parasitiformes are known from amber specimens dating to the mid- Cretaceous , around 100 million years ago. Most fossil acarids are no older than the Tertiary (up to 65 mya ). Members of the superorders Opilioacariformes and Acariformes (sometimes known as Actinotrichida) are mites, as well as some of
5445-417: The carbon cycle . Two species live on humans, namely Demodex folliculorum and Demodex brevis ; both are frequently referred to as eyelash mites. The majority of mite species are harmless to humans and domestic animals , but a few species can colonize mammals directly, acting as vectors for disease transmission, and causing or contributing to allergenic diseases. Mites which colonize human skin are
5544-638: The chelicerae , the pedipalps and the oral cavity. It is covered above by an extension of the body carapace and is connected to the body by a flexible section of cuticle . Two-segmented chelicerae is the ancestral condition in Acariformes, but in more derived groups they are single-segmented. And three-segmented chelicerae is the ancestral condition in Parasitiformes, but has been reduced to just two segments in more derived groups. The pedipalps differ between taxa depending on diet; in some species
5643-401: The chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. About 14% of these had been described by 2011. All species (except viruses ) are given a two-part name , called a "binomial". The first part of a binomial is the genus to which the species belongs. The second part
5742-399: The fly agaric . Natural hybridisation presents a challenge to the concept of a reproductively isolated species, as fertile hybrids permit gene flow between two populations. For example, the carrion crow Corvus corone and the hooded crow Corvus cornix appear and are classified as separate species, yet they can hybridise where their geographical ranges overlap. A ring species is
5841-507: The jaguar ( Panthera onca ) of Latin America or the leopard ( Panthera pardus ) of Africa and Asia. In contrast, the scientific names of species are chosen to be unique and universal (except for some inter-code homonyms ); they are in two parts used together : the genus as in Puma , and the specific epithet as in concolor . A species is given a taxonomic name when a type specimen
5940-516: The microscope by the English polymath Robert Hooke . In his 1665 book Micrographia , he stated that far from being spontaneously generated from dirt, they were "very prettily shap'd Insects". In 1898, Arthur Conan Doyle wrote a satirical poem, "A Parable", with the conceit of some cheese mites disputing the origin of the round cheddar cheese in which they all lived. The world's first science documentary featured cheese mites , seen under
6039-406: The "cynical species concept", and arguing that far from being cynical, it usefully leads to an empirical taxonomy for any given group, based on taxonomists' experience. Other biologists have gone further and argued that we should abandon species entirely, and refer to the "Least Inclusive Taxonomic Units" (LITUs), a view that would be coherent with current evolutionary theory. The species concept
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#17327932498876138-601: The Acari has been relatively little studied, but molecular information from ribosomal DNA is being extensively used to understand relationships between groups. The 18 S rRNA gene provides information on relationships among phyla and superphyla, while the ITS2 , and the 18S ribosomal RNA and 28S ribosomal RNA genes, provide clues at deeper levels. The mite fossil record is sparse, due to their small size and low preservation potential. The oldest fossils of acariform mites are from
6237-626: The Origin of Species explained how species could arise by natural selection . That understanding was greatly extended in the 20th century through genetics and population ecology . Genetic variability arises from mutations and recombination , while organisms themselves are mobile, leading to geographical isolation and genetic drift with varying selection pressures . Genes can sometimes be exchanged between species by horizontal gene transfer ; new species can arise rapidly through hybridisation and polyploidy ; and species may become extinct for
6336-405: The abbreviation "sp." in the singular or "spp." (standing for species pluralis , Latin for "multiple species") in the plural in place of the specific name or epithet (e.g. Canis sp.). This commonly occurs when authors are confident that some individuals belong to a particular genus but are not sure to which exact species they belong, as is common in paleontology . Authors may also use "spp." as
6435-570: The amount of hybridisation is insufficient to completely mix their respective gene pools . A further development of the recognition concept is provided by the biosemiotic concept of species. In microbiology , genes can move freely even between distantly related bacteria, possibly extending to the whole bacterial domain. As a rule of thumb, microbiologists have assumed that members of Bacteria or Archaea with 16S ribosomal RNA gene sequences more similar than 97% to each other need to be checked by DNA–DNA hybridisation to decide if they belong to
6534-552: The appendages resemble legs while in others they are modified into chelicerae-like structures. The oral cavity connects posteriorly to the mouth and pharynx . Most mites have four pairs of legs (two pairs in Eriophyoidea ), each with six segments, which may be modified for swimming or other purposes. The dorsal surface of the body is clad in hardened tergites and the ventral surface by hardened sclerites ; sometimes these form transverse ridges. The gonopore (genital opening)
6633-404: The appropriate sexes or mating types can produce fertile offspring , typically by sexual reproduction . It is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity . Other ways of defining species include their karyotype , DNA sequence, morphology , behaviour, or ecological niche . In addition, paleontologists use the concept of
6732-474: The biological species concept, "the several versions" of the phylogenetic species concept, and the idea that species are of the same kind as higher taxa are not suitable for biodiversity studies (with the intention of estimating the number of species accurately). They further suggested that the concept works for both asexual and sexually-reproducing species. A version of the concept is Kevin de Queiroz 's "General Lineage Concept of Species". An ecological species
6831-505: The biological species concept, a cladistic species does not rely on reproductive isolation – its criteria are independent of processes that are integral in other concepts. Therefore, it applies to asexual lineages. However, it does not always provide clear cut and intuitively satisfying boundaries between taxa, and may require multiple sources of evidence, such as more than one polymorphic locus, to give plausible results. An evolutionary species, suggested by George Gaylord Simpson in 1951,
6930-642: The body of honey bees , and Acarapis woodi (family Tarsonemidae ) lives in their tracheae . Hundreds of species are associated with other bees, mostly poorly described. They attach to bees in a variety of ways. For example, Trigona corvina workers have been found with mites attached to the outer face of their hind tibiae. Some are thought to be parasites, while others are beneficial symbionts . Mites also parasitize some ant species, such as Eciton burchellii . Most larvae of Parasitengona are ectoparasites of arthropods, while later life stages in this group tend to shift to being predators. Plant pests include
7029-428: The boundaries between closely related species become unclear with hybridisation , in a species complex of hundreds of similar microspecies , and in a ring species . Also, among organisms that reproduce only asexually , the concept of a reproductive species breaks down, and each clone is potentially a microspecies. Although none of these are entirely satisfactory definitions, and while the concept of species may not be
7128-407: The cause of several types of itchy skin rashes, such as gamasoidosis , rodent mite dermatitis , grain itch , grocer's itch , and scabies ; Sarcoptes scabiei is a parasitic mite responsible for scabies, which is one of the three most common skin disorders in children. Demodex mites, which are common cause of mange in dogs and other domesticated animals, have also been implicated in
7227-437: The commercially destructive Varroa parasite of honey bees , as well as scabies mites of humans. Most species are harmless to humans, but a few are associated with allergies or may transmit diseases. The scientific discipline devoted to the study of mites is called acarology . The mites are not a defined taxon, but is used for two distinct groups of arachnids, the Acariformes and the Parasitiformes . The phylogeny of
7326-433: The concept of a chronospecies can be applied. During anagenesis (evolution, not necessarily involving branching), some palaeontologists seek to identify a sequence of species, each one derived from the phyletically extinct one before through continuous, slow and more or less uniform change. In such a time sequence, some palaeontologists assess how much change is required for a morphologically distinct form to be considered
7425-434: The course of several days to months. As the season continues, these competing male choruses move to the evenings and cloudy, rainy days. The lifespan of these frogs averages five years. After mating has occurred, females can lay between 500 and 1500 eggs during the entire breeding season. The female lays one cluster at a time, which can contain 20–300 eggs. The eggs are retained in a loose, gelatinous cluster, submerged below
7524-428: The disease rickettsialpox . House dust mites , found in warm and humid places such as beds, cause several forms of allergic diseases, including hay fever , asthma and eczema , and are known to aggravate atopic dermatitis . Among domestic animals , sheep are affected by the mite Psoroptes ovis which lives on the skin, causing hypersensitivity and inflammation. Hay mites are a suspected reservoir for scrapie ,
7623-591: The entire dorsal side. The dorsal stripes can be broken up, reduced, or even absent in certain specimens. The white or cream-colored underside or ventral side of the frog typically has dark, scattered flecks. A single white stripe runs along the upper lip, and a heavy dark stripe runs across the eye and along each side from the snout to the leg. A dark triangular spot on the head may also be seen in some individuals. These frogs have small, round toes without pads and very little webbing between each toe. Typically, males are smaller than females , and can be told apart from
7722-435: The evidence to support hypotheses about evolutionarily divergent lineages that have maintained their hereditary integrity through time and space. Molecular markers may be used to determine diagnostic genetic differences in the nuclear or mitochondrial DNA of various species. For example, in a study done on fungi , studying the nucleotide characters using cladistic species produced the most accurate results in recognising
7821-417: The females by their yellow vocal sacs when calling. When not calling, this sac looks like a dark, loose flap of skin beneath the throat. Tadpoles of the western chorus frog have gray or brown bodies. Their body shape is round with clear tail fins and dark flecks. The intestinal coil reportedly can be seen through the belly skin if closely observed. Their lips are black. P. triseriata was once considered
7920-739: The frog's environment causes them to stop calling and dive into the depths of whatever water source they reside near, under leaf litter, logs, rocks, or loose soil, for minutes. These terrestrial hiding spots serve not only as hiding places, but also as hibernation places for the frogs during the winter. The diet of an adult consists of small invertebrates and arthropods , such as small flies, mosquitoes, ants, small beetles, moths and caterpillars, grasshoppers, and spiders, only if they are small enough. Froglets (the transition or metamorphic phase between tadpole and frog) will feed on smaller prey, such as mites , midges , and springtails . Tadpoles feed on periphyton, filamentous algae, diatoms, and pollen in or on
8019-417: The human skin disease rosacea , although the mechanism by which demodex contributes to the disease is unclear. Ticks are well known for carrying diseases, such as Lyme disease and Rocky Mountain spotted fever . Chiggers are known primarily for their itchy bite , but they can also spread disease in some limited circumstances, such as scrub typhus . The house-mouse mite is the only known vector of
8118-430: The larval or adult forms could indicate pollution or toxic substances in the environment, sometimes trematodes . Therefore, the health of these frogs are valuable in determining the health of ecosystems and whether agricultural practices have leaked any pesticides, herbicides, or fertilizers into the environment. Species A species ( pl. : species) is a population of organisms in which any two individuals of
8217-612: The most diverse and successful of all invertebrate groups. They have exploited a wide array of habitats , and because of their small size go largely unnoticed. They are found in freshwater (e.g. the water mites or Hydrachnidia ) and saltwater (most Halacaridae ), in the soil, in forests, pastures, agricultural crops, ornamental plants, thermal springs and caves. They inhabit organic debris of all kinds and are extremely numerous in leaf litter. They feed on animals, plants and fungi and some are parasites of plants and animals. Some 48,200 species of mites have been described, but there may be
8316-506: The nests of birds and other animals. These mites are largely parasitic and consume blood , skin and keratin . Dust mites , which feed mostly on dead skin and hair shed from humans instead of consuming them from the organism directly, evolved from these parasitic ancestors. Ticks are a prominent group of mites that are parasitic on vertebrates, mostly mammal and birds, feeding on blood with specialised mouthparts. Parasitic mites sometimes infest insects. Varroa destructor attaches to
8415-483: The numerous fungi species of all the concepts studied. Versions of the phylogenetic species concept that emphasise monophyly or diagnosability may lead to splitting of existing species, for example in Bovidae , by recognising old subspecies as species, despite the fact that there are no reproductive barriers, and populations may intergrade morphologically. Others have called this approach taxonomic inflation , diluting
8514-593: The paper is accepted for publication. The type material is usually held in a permanent repository, often the research collection of a major museum or university, that allows independent verification and the means to compare specimens. Describers of new species are asked to choose names that, in the words of the International Code of Zoological Nomenclature , are "appropriate, compact, euphonious, memorable, and do not cause offence". Books and articles sometimes intentionally do not identify species fully, using
8613-674: The person who named the species, while the antonym sensu lato ("in the broad sense") denotes a wider usage, for instance including other subspecies. Other abbreviations such as "auct." ("author"), and qualifiers such as "non" ("not") may be used to further clarify the sense in which the specified authors delineated or described the species. Species are subject to change, whether by evolving into new species, exchanging genes with other species, merging with other species or by becoming extinct. The evolutionary process by which biological populations of sexually-reproducing organisms evolve to become distinct or reproductively isolated as species
8712-413: The phylogenetic tree, as shown below. Palpigradi False scorpions [REDACTED] Ixodida (ticks) [REDACTED] Parasitic mites, inc. Varroa [REDACTED] Trombidiformes (chiggers, velvet mites, etc) [REDACTED] Sarcoptiformes (dust & fur mites, etc) [REDACTED] Camel spiders [REDACTED] other Arachnids including spiders and scorpions However,
8811-487: The result of misclassification leading to questions on whether there really are any ring species. The commonly used names for kinds of organisms are often ambiguous: "cat" could mean the domestic cat, Felis catus , or the cat family, Felidae . Another problem with common names is that they often vary from place to place, so that puma, cougar, catamount, panther, painter and mountain lion all mean Puma concolor in various parts of America, while "panther" may also mean
8910-586: The ring. Ring species thus present a difficulty for any species concept that relies on reproductive isolation. However, ring species are at best rare. Proposed examples include the herring gull – lesser black-backed gull complex around the North pole, the Ensatina eschscholtzii group of 19 populations of salamanders in America, and the greenish warbler in Asia, but many so-called ring species have turned out to be
9009-508: The same species. This concept was narrowed in 2006 to a similarity of 98.7%. The average nucleotide identity (ANI) method quantifies genetic distance between entire genomes , using regions of about 10,000 base pairs . With enough data from genomes of one genus, algorithms can be used to categorize species, as for Pseudomonas avellanae in 2013, and for all sequenced bacteria and archaea since 2020. Observed ANI values among sequences appear to have an "ANI gap" at 85–95%, suggesting that
9108-529: The same species. When two species names are discovered to apply to the same species, the older species name is given priority and usually retained, and the newer name considered as a junior synonym, a process called synonymy . Dividing a taxon into multiple, often new, taxa is called splitting . Taxonomists are often referred to as "lumpers" or "splitters" by their colleagues, depending on their personal approach to recognising differences or commonalities between organisms. The circumscription of taxa, considered
9207-564: The six-legged larvae. After three moults, the larvae become nymphs, with eight legs, and after a further three moults, they become adults. Longevity varies between species, but the lifespan of mites is short compared to many other arachnids. Mites occupy a wide range of ecological niches . For example, Oribatida mites are important decomposers in many habitats. They eat a wide variety of material including living and dead plant and fungal material, lichens and carrion; some are predatory , though no oribatid mites are parasitic . Mites are among
9306-477: The so-called spider mites (family Tetranychidae ), thread-footed mites (family Tarsonemidae ), and the gall mites (family Eriophyidae ). Among the species that attack animals are members of the sarcoptic mange mites (family Sarcoptidae ), which burrow under the skin. Demodex mites (family Demodecidae ) are parasites that live in or near the hair follicles of mammals , including humans. Being unable to fly, mites need some other means of dispersal. On
9405-456: The species concept and making taxonomy unstable. Yet others defend this approach, considering "taxonomic inflation" pejorative and labelling the opposing view as "taxonomic conservatism"; claiming it is politically expedient to split species and recognise smaller populations at the species level, because this means they can more easily be included as endangered in the IUCN red list and can attract conservation legislation and funding. Unlike
9504-505: The stigmata are associated with peritremes: paired, tubular, elaborated extensions of the tracheal system. The higher taxa of mites are defined by these structures: Mite digestive systems have salivary glands that open into the preoral space rather than the foregut. Most species carry two to six pairs of salivary glands that empty at various points into the subcheliceral space. A few mite species lack an anus: they do not defecate during their short lives. The circulatory system consists of
9603-564: The surface of the water. They will scavenge if given the opportunity. Breeding occurs at different times throughout the various states where this frog resides. Typically, western chorus frog's breeding season starts in March through May, with April being the most active month. However, breeding takes place earlier in southern parts and can vary through the frogs entire range. The earliest sign of western chorus frog breeding occurs with choruses heard on sunny days. Males call to potential females over
9702-611: The water and stuck to weeds or grasses found along the edges of shallow ponds, flooded swales , roadside ditches, flooded fields, open areas, and swamps. The eggs will hatch into tadpoles between three and 14 days after being laid. However, water temperature can be a limiting factor in the growth of both eggs and tadpoles. Colder water temperatures prevent the tadpoles and eggs from growing. Tadpoles metamorphose into froglets 40–90 days afterwards. Although quite adaptable and tolerant to human activity, western chorus frog populations are declining in certain areas. Labeled as in least concern on
9801-540: The wild. It is difficult to define a species in a way that applies to all organisms. The debate about species concepts is called the species problem. The problem was recognised even in 1859, when Darwin wrote in On the Origin of Species : I was much struck how entirely vague and arbitrary is the distinction between species and varieties. He went on to write: No one definition has satisfied all naturalists; yet every naturalist knows vaguely what he means when he speaks of
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