taxonomic rank that includes species but not families
genus
11282542
one rank below species. Today, nomenclature is regulated by the nomenclature codes. There are seven main taxonomic ranks: kingdom, phylum or division, class, order, family, genus, species. In addition, "domain" (proposed by Carl Woese) is now widely used as a fundamental rank, although it is not mentioned in any of the nomenclature codes, and is a synonym for dominion (lat. dominium), introduced by Moore in 1974. A taxon is usually assigned a rank when it is given its formal name. The basic ranks are species and genus. When an organism is given a species name it is assigned to a
Taxonomic rank
11282552
can't be supplied with names. This problem is dissolved in cladoendesis, where the specially elaborated rank-free nomenclatures are used. There are no rules for how many species should make a genus, a family, or any other higher taxon (that is, a taxon in a category above the species level). It should be a natural group (that is, non-artificial, non-polyphyletic), as judged by a biologist, using all the information available to them. Equally ranked higher taxa in different phyla are not necessarily equivalent (e.g., it is incorrect to assume that families of insects are in some way evolutionarily comparable to families
Taxonomic rank
11282539
Taxonomic rank In biological classification, taxonomic rank is the relative level of a group of organisms (a taxon) in a taxonomic hierarchy. Examples of taxonomic ranks are species, genus, family, order, class, phylum, kingdom, domain, etc. A given rank subsumes under it less general categories, that is, more specific descriptions of life forms. Above it, each rank is classified within more general categories of organisms and groups of organisms related to each other through inheritance of traits or features from common ancestors. The rank of any "species" and the description of its "genus" is "basic"; which means that to identify
Taxonomic rank
11282540
a particular organism, it is usually not necessary to specify ranks other than these first two. Consider a particular species, the red fox, "Vulpes vulpes": the next rank above, the genus "Vulpes", comprises all the "true" foxes. Their closest relatives are in the immediately higher rank, the family Canidae, which includes dogs, wolves, jackals, and all foxes; the next higher rank, the order Carnivora, includes caniforms (bears, seals, weasels, skunks, raccoons and all those mentioned above), and feliforms (cats, civets, hyenas, mongooses). Carnivorans are one group of the hairy, warm-blooded, nursing members of the class Mammalia, which are classified among
Taxonomic rank
1623221
a narrow set of ranks is challenged by users of cladistics; for example, the mere 10 ranks traditionally used between animal families (governed by the ICZN) and animal phyla (usually the highest relevant rank in taxonomic work) often cannot adequately represent the evolutionary history as more about a lineage's phylogeny becomes known. In addition, the class rank is quite often not an evolutionary but a phenetic or paraphyletic group and as opposed to those ranks governed by the ICZN (family-level, genus-level and species-level taxa), can usually not be made monophyletic by exchanging the taxa contained therein. This has given rise
Taxon
11282541
animals with backbones in the phylum Chordata, and with them among all animals in the kingdom Animalia. Finally, at the highest rank all of these are grouped together with all other organisms possessing cell nuclei in the domain Eukarya. The "International Code of Zoological Nomenclature" defines "rank" as: "The level, for nomenclatural purposes, of a taxon in a taxonomic hierarchy (e.g. all families are for nomenclatural purposes at the same rank, which lies between superfamily and subfamily)." In his landmark publications, such as the "Systema Naturae", Carl Linnaeus used a ranking scale limited to: kingdom, class, order, genus, species, and
Taxonomic rank
11282542
one rank below species. Today, nomenclature is regulated by the nomenclature codes. There are seven main taxonomic ranks: kingdom, phylum or division, class, order, family, genus, species. In addition, "domain" (proposed by Carl Woese) is now widely used as a fundamental rank, although it is not mentioned in any of the nomenclature codes, and is a synonym for dominion (lat. dominium), introduced by Moore in 1974. A taxon is usually assigned a rank when it is given its formal name. The basic ranks are species and genus. When an organism is given a species name it is assigned to a
Taxonomic rank
11282553
of mollusks). For animals, at least the phylum rank is usually associated with a certain body plan, which is also, however, an arbitrary criterion. Taxonomic rank In biological classification, taxonomic rank is the relative level of a group of organisms (a taxon) in a taxonomic hierarchy. Examples of taxonomic ranks are species, genus, family, order, class, phylum, kingdom, domain, etc. A given rank subsumes under it less general categories, that is, more specific descriptions of life forms. Above it, each rank is classified within more general categories of organisms and groups of organisms related to each other through inheritance of
Taxonomic rank
1396427
smaller genus "Mullerornis". All these species went into decline following the arrival of humans on Madagascar around 2000 years ago, and were gone by the 17th or 18th century if not earlier. There are two taxonomic approaches to ratite classification: the one applied here combines the groups as families in the order Struthioniformes, while the other supposes that the lineages evolved mostly independently and thus elevates the families to order rank (e.g. Rheiformes, Casuariformes etc.). The longstanding story of their evolution suggests that they share a common flightless ancestor that lived on Gondwana, whose descendants were carried by continental drift
Ratite
11282543
genus, and the genus name is part of the species name. The species name is also called a binomial, that is, a two-term name. For example, the zoological name for the human species is "Homo sapiens". This is usually italicized in print and underlined when italics are not available. In this case, "Homo" is the generic name and it is capitalized; "sapiens" indicates the species and it is not capitalized. There are definitions of the following taxonomic ranks in the International Code of Zoological Nomenclature: superfamily, family, subfamily, tribe, subtribe, genus, subgenus, species, subspecies. The International Code of Zoological Nomenclature
Taxonomic rank
532669
transitional forms are particularly unstable, and thereby perish rapidly and completely. Although quantum evolution may happen at any taxonomic level, it plays a much larger role in "the origin taxonomic units of relatively high rank, such as families, orders, and classes." Usage of the phrase "quantum evolution" in plants was apparently first articulated by Verne Grant in 1963 (pp. 458-459). He cited an earlier 1958 paper by Harlan Lewis and Peter H. Raven, wherein Grant asserted that Lewis and Raven gave a "parallel" definition of quantum evolution as defined by Simpson. Lewis and Raven postulated that species in the Genus
Quantum evolution
359377
the results of molecular phylogenetic studies of DNA sequences. It is not part of any of the classification systems based on plant morphology. The group is much in need of comparative anatomical study, especially in light of the recent expansion of the family Peridiscaceae to include "Medusandra", a genus that before 2009 had usually not been placed in Saxifragales. The order is divided into suprafamilial groups as shown on the phylogenetic tree below. These groups are informal and are not understood to have any particular taxonomic rank. Saxifragales contain about 2470 species. These are distributed into 15 families, or into
Saxifragales
10527975
Stylidium sect. Tenella "Stylidium" section Tenella is a taxonomic rank in the plant kingdom under "Stylidium" subgenus "Andersonia". In 2000, A.R. Bean published a taxonomic revision of subgenus "Andersonia" and established this section to separate these eleven species based on morphological and cladistic analysis. This taxonomic rank is named after George Bentham's series "Tenellae", which he established in his 1869 treatment of the family Stylidiaceae. Series "Tenellae" was not used in Johannes Mildbraed's 1908 taxonomic monograph in which he completely revised the subgeneric taxonomy of the genus. Mildbraed's treatment of the genus taxonomy is the general demarcation which has been
Stylidium sect. Tenella
6189635
Samolus Samolus (known as brookweed, or water pimpernel) is a widely distributed genus of about a dozen species of water-loving herbs. According to the APG III classification, this genus belongs to the Primulaceae family in the order Ericales. It was considered as closely related to a clade comprising the Theophrastaceae, and was treated as part of that family or in its own monogeneric family, the Samolaceae. The APG III system does not recognize these families and instead includes all species formerly belonging to Theophrastaceae in the Primulaceae family. The last complete taxonomic treatment of this genus recognizes the following species:
Samolus
10728926
to the taxonomic rank of genus by Horton H. Hobbs, Jr., who later erected most of the subgenera now recognised within the genus, in his 1972 monograph "The subgenera of the crayfish genus "Procambarus" (Decapoda: Astacidae)". Procambarus Procambarus is a genus of crayfish in the family Cambaridae, all native to North and Central America. It includes a number of troglobitic species, and the marbled crayfish ("marmorkrebs"), which is parthenogenetic. Originally described as a subgenus for four species, it now contains 161 species in 16 subgenera. The majority of the diversity is found in the southeastern United States, but the genus
Procambarus
7175166
Colostethus Colostethus is a genus of poison dart frogs native to Central and South America, from Panama south to Colombia, Ecuador, and northern Peru. Their common name is rocket frogs, but this name may refer to frogs in other genera and families, following the taxonomic revision of the genus in 2006. "Colostethus" was found to be "rampantly nonmonophyletic" in the taxonomic revision of poison dart frogs published in 2006. Before the revision, it had 138 species, but this was reduced to 18 species, after the former "Colostethus" were distributed among eight genera in two families, that is, in Dendrobatidae and
Colostethus
14023110
Diplazium Diplazium is a genus of ferns that specifically includes the approximately 400 known species of twinsorus ferns. The Greek root is "diplazein" meaning "double": the indusia in this genus lie on both sides of the vein. These ferns were earlier considered part of either the Athyriaceae, Dryopteridaceae, Aspleniaceae, or Polypodiaceae families but are often recognized as belonging to their own taxonomic family. The taxonomy of the genus is difficult and poorly known, and by 2009 has never been the subject of a complete monographic study. Their distribution is pantropical, with a few species extending into temperate areas. The rhizome
Diplazium
16014549
of 7, 8, or 9 as in the other Rosaceae. There are approximately 28 genera that contain about 1100 species worldwide, with most species occurring in the temperate Northern Hemisphere. The name Maleae is required by the International Code of Nomenclature for algae, fungi, and plants (article 19), for any group at the tribal level that includes the genus "Malus", but not either of the genera "Rosa" or "Amygdalus". A traditional circumscription of Maleae includes the following genera: intergeneric hybrids: and graft hybrids:<br> "+Pyrocydonia" ("Pirocydonia") A recent taxonomic treatment includes the following genera in Maleae that were earlier separated as
Maleae
11282547
rank of species and above (but below genus) have a botanical name in two parts (binary name); all taxa below the rank of species have a botanical name in three parts (an infraspecific name). To indicate the rank of the infraspecific name, a "connecting term" is needed. Thus "Poa secunda" subsp. "juncifolia", where "subsp." is an abbreviation for "subspecies", is the name of a subspecies of "Poa secunda". Hybrids can be specified either by a "hybrid formula" that specifies the parentage, or may be given a name. For hybrids receiving a hybrid name, the same ranks apply, prefixed with "notho"
Taxonomic rank
132547
Equidae Equidae (sometimes known as the horse family) is the taxonomic family of horses and related animals, including the extant horses, donkeys, and zebras, and many other species known only from fossils. All extant species are in the genus "Equus". Equidae belongs to the order Perissodactyla, which includes the extant tapirs and rhinoceros, and several extinct families. The term equid refers to any member of this family, including any equine. The oldest known fossils assigned to Equidae date from the early Eocene, 54 million years ago. They used to be assigned to the genus "Hyracotherium", but the type species of
Equidae
17106141
placed in the tribe Tecomeae, but that tribe has been greatly reduced to only 11 or 12 genera and no longer includes "Handroanthus". "Handroanthus" is one of the 12 to 14 genera that make up a group informally known as the "Tabebuia" alliance. This group has not been assigned to any taxonomic rank, and neither has Crescentiina, the smallest group that it is a member of. Cladistic analysis of DNA data has strongly supported "Handroanthus", but sampling of taxa and DNA has not been sufficient to strongly support any relationships within the genus. Handroanthus Handroanthus is a genus of flowering
Handroanthus
8110845
to some species of "B." ser. "Dryandra" (formerly given genus rank as "Dryandra"). Sweet did not designate a type specimen for the species. Australian botanist Alex George has since designated as neotype one of Baxter's specimen sheets located at the British Museum (Natural History), labelled "Banksia new Seeds marked Dryandroides". The species has an uneventful taxonomic history. No subspecies or varieties have been identified; it has no taxonomic synonyms; and its only nomenclatural synonym is ""Sirmuellera dryandroides" (Sweet.) Kuntze", which arose from Otto Kuntze's unsuccessful 1891 attempt to transfer "Banksia" into the new name "Sirmuellera". Sweet placed "B. dryandroides" in
Banksia dryandroides
11282546
an indeterminate number of ranks. The ICN explicitly mentions: primary ranks kingdom ("regnum") division or phylum ("divisio", "phylum") class ("classis") order ("ordo") family ("familia") genus ("genus") species ("species") There are definitions of the following taxonomic categories in the International Code of Nomenclature for Cultivated Plants: cultivar group, cultivar, grex. The rules in the ICN apply primarily to the ranks of family and below, and only to some extent to those above the rank of family. Also see descriptive botanical names. Taxa at the rank of genus and above have a botanical name in one part (unitary name); those at the
Taxonomic rank
11282544
divides names into "family-group names", "genus-group names" and "species-group names". The Code explicitly mentions the following ranks for these categories: "Family" "Genus" "Species" The rules in the Code apply to the ranks of superfamily to subspecies, and only to some extent to those above the rank of superfamily. Among "genus-group names" and "species-group names" no further ranks are officially allowed. Zoologists sometimes use additional terms such as "species group", "species subgroup", "species complex" and "superspecies" for convenience as extra, but unofficial, ranks between the subgenus and species levels in taxa with many species, e.g. the genus "Drosophila". (Note the potentially
Taxonomic rank
3742764
as being in special need of phylogenetic study. The basal epidendroids, especially the tribe Gastrodieae, remain poorly sampled in phylogenetic studies. The orchid family (Orchidaceae) is subdivided into five subfamilies, and then into tribes and subtribes. Groups of closely related genera are sometimes referred to informally as alliances. An alliance is a group of taxa, at any taxonomic rank, but usually at the rank of genus or species, that are thought to be closely related. Alliances are designated provisionally and are not recognized in the ICNAFP. The subtribes are formally divided into genera. Some of the genera are divided into
Taxonomy of the Orchidaceae
10659776
Colius Colius is a bird genus in the family Coliidae. It contains the following species: A fossil species, "Colius hendeyi", was described from Early Pliocene remains found at Langebaanweg in South Africa. Some Miocene taxa from France were previously assigned to "Colius". Of these, only the Middle Miocene ""Colius" palustris" might plausibly belong there, but it is more often separated in "Necrornis". In younger lineages like Passeriformes, extant genera (e.g. "Menura" and "Orthonyx") were around by then, though it must be remembered that simply because two taxa are of same taxonomic rank they do not need to be of the
Colius
11614249
"Torricellia" in 2004, resulting in the transfer of the first two of these genera into Torricelliaceae. Aralidium Aralidium is a genus in the plant family Torricelliaceae. It includes the single species Aralidium pinnatifidum, a small tree or shrub distributed in southeastern Asia, Malaysia, and Indonesia. Taxonomic placement of this genus has proven difficult because it possesses characters in common with both the Araliaceae and Cornaceae. In the Cronquist system, it was placed in Cornaceae, but the APG II system give it its own family, Aralidiaceae, with the proviso that "[s]ome of the families are monogeneric and could possibly be merged
Aralidium
737021
Class (biology) In biological classification, class () is a taxonomic rank, as well as a taxonomic unit, a taxon, in that rank. Other well-known ranks in descending order of size are life, domain, kingdom, phylum, order, family, genus, and species, with class fitting between phylum and order. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the prefix "sub-": subclass (Latin: "subclassis"). For example, dogs are in the class Mammalia. The composition of each class is determined by a taxonomist. Often there is no exact agreement, with different taxonomists taking different positions.
Class (biology)
7509238
having erected the genus "Hesperoyucca", but others credit this to William Trelease, who printed a taxonomic description in 1893, formally recognising "Hesperoyucca" as being at the same rank as, but separate from, "Yucca". It has taken recent DNA analysis to confirm that they are indeed genetically distinct from "Yucca". The splitting of "Hesperoyucca" from "Yucca" is still not widely reflected in available literature or online (for example, the British Royal Botanic Gardens, Kew and the Royal Horticultural Society websites do not recognise the name as current). Hesperoyucca Hesperoyucca is a small genus of two recognized species of flowering plants closely
Hesperoyucca
16666304
the other classes with their orders, families, etc.", or a family with one genus and one species, or a class with one order and one genus, etc. Agassiz concludes a single species is sufficient to derive the entirety of the hierarchy: at the time, this would have been "a distinct genus, a distinct family, a distinct class, a distinct branch." The point of the sunfish is not observing characteristics that distinguish individuals, species and genus, but rather characteristics that are held in common higher up the taxonomic hierarchy. Scudder's observation that finally satisfies Agassiz is that the sunfish has bilateral,
Parable of the Sunfish
18611557
Scleractinian Families "Micrabaciidae" and "Fungiidae" and their Taxonomic and Ecologic Implications." She received her PhD from George Washington University in 1984. Now publishing as Joan Murrell Owens, she continued her laboratory work at the Smithsonian, classifying and studying button corals, while advancing to the rank of associate professor in the department of geology and geography at Howard University in 1986. She described the new genus "Rhombopsammia" and its two species in 1986, and added a new species to the genus "Letepsammia" in 1994, naming "L. franki" for her husband, Frank A. Owens. Both genera are in the family Micrabaciidae. Joan
Joan Murrell Owens
14155949
was originally placed in the Trapeziidae. Tanaocheles Tanaocheles is a genus of crabs, the only genus in the family Tanaocheleidae. It contains two species, "T. bidentata" and "T. stenochilus". The two species were formerly placed in different families, and they were only shown to be related, and placed in a new subfamily (now elevated to the taxonomic rank of family), in 2000. Originally described as "Chlorodius bidentatus", and later called "Chlorodiella bidentata", Tanaocheles bidentata was assigned for a long time to the Xanthidae. Tanaocheles stenochilus was described in 1989 from material collected in Guam, where it lives among colonies of
Tanaocheles
14155948
Tanaocheles Tanaocheles is a genus of crabs, the only genus in the family Tanaocheleidae. It contains two species, "T. bidentata" and "T. stenochilus". The two species were formerly placed in different families, and they were only shown to be related, and placed in a new subfamily (now elevated to the taxonomic rank of family), in 2000. Originally described as "Chlorodius bidentatus", and later called "Chlorodiella bidentata", Tanaocheles bidentata was assigned for a long time to the Xanthidae. Tanaocheles stenochilus was described in 1989 from material collected in Guam, where it lives among colonies of the stony coral "Leptoseris gardineri". It
Tanaocheles
11614248
Aralidium Aralidium is a genus in the plant family Torricelliaceae. It includes the single species Aralidium pinnatifidum, a small tree or shrub distributed in southeastern Asia, Malaysia, and Indonesia. Taxonomic placement of this genus has proven difficult because it possesses characters in common with both the Araliaceae and Cornaceae. In the Cronquist system, it was placed in Cornaceae, but the APG II system give it its own family, Aralidiaceae, with the proviso that "[s]ome of the families are monogeneric and could possibly be merged when well-supported sister-group relationships have been established." Such a relationship was established between "Aralidium", "Melanophylla" and
Aralidium
11644242
Utricularia sect. Aranella Utricularia" sect. "Aranella is a section in the genus "Utricularia". The ten species in this section are small terrestrial carnivorous plants native to tropical South America with one species also extending into tropical Africa. John Hendley Barnhart originally described and published this section in 1913 as a separate genus, "Aranella". Sadashi Komiya revised the genus "Utricularia" in a 1973 taxonomic review and placed Barnhart's genus at the rank of subgenus within "Utricularia". Peter Taylor then published his taxonomic monograph of "Utricularia" in 1986 in which he reduced Komiya's subgenus to the rank of section, placing it within
Utricularia sect. Aranella
13673352
Bosellia Bosellia is a genus of sea slugs, marine gastropod mollusks within the superfamily Plakobranchoidea. "Bosellia" is the only genus in the family Boselliidae. Such families are monotypic families and this family has no subfamilies. Distribution include warm waters in Mediterranean and in Atlantic ocean. Reports from Indo-Pacific were not confirmed. Species within the genus "Bosellia" include 3 species and one with uncertain taxonomic status: Phylogenetic results by Händeler et al. (2009) indicate that the Caribbean ""Bosellia marcusi"" described by Eveline Agnes du Bois-Reymond Marcus (1972) is a derived species of "Elysia". Morphological examination indicates that the parapodia of ""B.
Bosellia
9123527
Banksia ser. Cyrtostylis Banksia" ser. "Cyrtostylis is a taxonomic series within the plant genus "Banksia". First published at sectional rank by George Bentham in 1870, it was demoted to a series by Alex George in 1981. The name has had three circumscriptions. Bentham published B." sect. "Cyrtostylis in "Flora Australiensis", as part of his taxonomic arrangement of "Banksia", defining it as those taxa with This definition essentially defined "Cyrtostylis" as a section for those species that did not possess the characters of the other sections; thus it was highly heterogeneous. George Bentham's placement and circumscription of "B." sect. "Cyrtostylis" may
Banksia ser. Cyrtostylis
7297615
families in the Asiloidea, to establish consistent phylogenetic relationships. The Therevidae now constitute a monophyletic clade that English-speaking dipterologists call the therevoid clade (clade of "Terevoidi"). This group has not been assigned a ranking at any taxonomic level above the rank of family, but for the present is recognised as a group of families within the superfamily Asiloidea. Therevoid clade Clade showing relationship of Asiloidea At present, over 1, 600 species are known. After taxonomic revisions by Lyneborg (1976) and Winterston et al. (2001), the family is divided into four subfamilies, among which the most representative in size and diffusion
Therevidae
11282550
purposes of demonstration of relative rank (but see notes), from most general to most specific: Ranks are assigned based on subjective dissimilarity, and do not fully reflect the gradational nature of variation within nature. In most cases, higher taxonomic groupings arise further back in time: not because the rate of diversification was higher in the past, but because each subsequent diversification event results in an increase of diversity and thus increases the taxonomic rank assigned by present-day taxonomists. Furthermore, some groups have many described species not because they are more diverse than other species, but because they are more easily
Taxonomic rank
15384897
Taxonomic inflation Taxonomic inflation is a pejorative term for what is perceived to be an excessive increase in the number of recognised taxa in a given context, due not to the discovery of new taxa but rather to putatively arbitrary changes to how taxa are delineated. The best known case is the elevation of a group of subspecies to species rank, through the arbitrary decision that the differences between the various taxa warrant distinguishing them at species rank. Taxonomic inflation is often claimed to occur for conservation reasons. It may be difficult to make a case for the protection of
Taxonomic inflation
15384898
an isolated and unusual population of a common and widespread species, but it becomes much easier to do so if that population is recognised as a rare subspecies or species. Taxonomic inflation Taxonomic inflation is a pejorative term for what is perceived to be an excessive increase in the number of recognised taxa in a given context, due not to the discovery of new taxa but rather to putatively arbitrary changes to how taxa are delineated. The best known case is the elevation of a group of subspecies to species rank, through the arbitrary decision that the differences between the
Taxonomic inflation
13097701
the varied uses of the concept of species, and that the solution is to abandon it and all other taxonomic ranks, and use unranked monophyletic groups instead. It has been argued, too, that since species are not comparable, counting them is not a valid measure of biodiversity; alternative measures of phylogenetic biodiversity have been proposed. Species In biology, a species is the basic unit of classification and a taxonomic rank, as well as a unit of biodiversity, but it has proven difficult to find a satisfactory definition. Scientists and conservationists need a species definition which allows them to work, regardless
Species
16189686
unusual in the "Cryptococcus" family in that it can weakly ferment D-glucose, D-galactose, maltose and melezitose. This species is DBB+. "C. aquaticus" has been studied because of its ability to produce pecticase. It produces polycalacturonase, but not isoenzymes of polygalacturonase, and it has increased activity in the presence of glucose. This species of "Cryptococcus" has an interested trait in that it produces mycocins, which are proteinacous toxins that either kill or inhibit the ability of fungi that are in the same taxonomic rank or in a related taxonomic rank. The mycocin that "C. aquaticus" produces was only able to kill
Cryptococcus aquaticus
8263545
in these sequences are often introduced by new publications. Taxonomic sequence Taxonomic sequence (also known as systematic, phyletic or taxonomic order) is a sequence followed in listing of taxa which aids ease of use and roughly reflects the evolutionary relationships among the taxa. Taxonomic sequences can exist for taxa within any rank, that is, a list of families, genera, species can each have a sequence. Early biologists used the concept of "age" or "primitiveness" of the groups in question to derive an order of arrangement, with "older" or more "primitive" groups being listed first and more recent or "advanced" ones
Taxonomic sequence
8263543
Taxonomic sequence Taxonomic sequence (also known as systematic, phyletic or taxonomic order) is a sequence followed in listing of taxa which aids ease of use and roughly reflects the evolutionary relationships among the taxa. Taxonomic sequences can exist for taxa within any rank, that is, a list of families, genera, species can each have a sequence. Early biologists used the concept of "age" or "primitiveness" of the groups in question to derive an order of arrangement, with "older" or more "primitive" groups being listed first and more recent or "advanced" ones last. A modern understanding of evolutionary biology has brought
Taxonomic sequence
13095566
Two superfamilies belongs to clade Sigmurethra, but they are not in the limacoid clade. After excluding groups not related, the informal group Sigmurethra becomes Suborder Helicina, with the following nine infraorders and a collection of families with no superfamily： Sigmurethra Sigmurethra is a taxonomic category of air-breathing land snails and slugs, terrestrial pulmonate gastropod molluscs. This is an informal group which includes the majority of land snails and slugs. The two strong synapomorphies of Sigmurethra are a long pedal gland placed beneath a membrane and retractile tentacles. Several families in this group contain species of snails and slugs that create
Sigmurethra
11282551
sampled and studied than other group. Of these many ranks, the most basic is species. However, this is not to say that a taxon at any other rank may not be sharply defined, or that any species is guaranteed to be sharply defined. It varies from case to case. Ideally, a taxon is intended to represent a clade, that is, the phylogeny of the organisms under discussion, but this is not a requirement. Classification, in which all taxa have formal ranks, cannot adequately reflect knowledge about phylogeny; at the same time, if taxon names are dependent on ranks, rank-free taxa
Taxonomic rank
13175997
Amborellales, Nymphaeales, and Austrobaileyales. These constitute a paraphyletic grade called basal angiosperms. The order names, ending in -ales are used here without reference to taxonomic rank because these groups contain only one order. Mesangiospermae includes the following clades: The mesangiosperms are usually recognized in classification systems that do not assign groups to taxonomic rank. The name Mesangiospermae is a branch-modified node-based name in phylogenetic nomenclature. It is defined as the most inclusive crown clade containing "Platanus occidentalis", but not "Amborella trichopoda", "Nymphaea odorata", or "Austrobaileya scandens". It is sometimes written as /Mesangiospermae even though this is not required by the
Mesangiospermae
20522172
Informal group (taxonomy) In taxonomy, an informal group is not a well defined taxonomic rank. This type of group can be paraphyletic or polyphyletic but is kept for ease, pending new systems of classification. Examples can be found in the classification of gastropods: Opisthobranchia, Sorbeoconcha, Hypsogastropoda and Ptenoglossa are informal groups nearby the level of the order. In human taxonomy, the informal taxonomic rank of race is variously considered equivalent or subordinate to the rank of subspecies. An alliance is also considered an informal grouping of species, genera or tribes to which authors wish to refer, that have at some
Informal group (taxonomy)
19867749
under the ICZN, but in 2006, Smith suggested that the name Canthonini, though junior, might be preserved under Code Article 35.5, which can be used to preserve junior names if they are higher in taxonomic rank than the senior names of constituent taxa. However, this Article does not apply when two names are competing for the same taxonomic rank (as in this case, both being used at the rank of tribe), so this conclusion has been reversed by subsequent classifications, restoring Deltochilini as the valid name. The tribe comprises about 800 species in 120 genera: They constitute a high proportion
Deltochilini
4938903
Index Kewensis The Index Kewensis (IK), maintained by the Royal Botanic Gardens, Kew, is a publication that aims to register all botanical names for seed plants at the rank of species and genera. It later came to include names of taxonomic families and ranks below that of species. The "Index" is currently maintained as part of the International Plant Names Index in combination with the Gray Herbarium and Australian Plant Name indexes. This database is anticipated to complete the task of creating a complete list of plant names, although it does not determine which are accepted species names. The preparation
Index Kewensis
10527976
used in subsequent revisions and additions. Species in this section have sessile leaves that are often minute, bract-like, and rarely form rosettes. Scapes are very short or mostly absent. Stylidium sect. Tenella "Stylidium" section Tenella is a taxonomic rank in the plant kingdom under "Stylidium" subgenus "Andersonia". In 2000, A.R. Bean published a taxonomic revision of subgenus "Andersonia" and established this section to separate these eleven species based on morphological and cladistic analysis. This taxonomic rank is named after George Bentham's series "Tenellae", which he established in his 1869 treatment of the family Stylidiaceae. Series "Tenellae" was not used in
Stylidium sect. Tenella
5313810
Race (biology) In biological taxonomy, race is an informal rank in the taxonomic hierarchy, below the level of subspecies. It has been used as a higher rank than strain, with several strains making up one race. Various definitions exist. Races may be genetically distinct populations of individuals within the same species, or they may be defined in other ways, e.g. geographically, or physiologically. Genetic isolation between races is not complete, but genetic differences may have accumulated that are not (yet) sufficient to separate species. The term is recognized by some, but not governed by any, of the formal codes of
Race (biology)
3214
contained only five families, of which only two are retained in the APG III classification. Under the Cronquist system of taxonomic classification of flowering plants, Asteraceae was the only family in the group, but newer systems (such as APG II and APG III) have expanded it to 11. In the classification system of Dahlgren the Asterales were in the superorder Asteriflorae (also called Asteranae). The order Asterales currently includes 11 families, the largest of which are the Asteraceae, with about 25,000 species, and the Campanulaceae ("bellflowers"), with about 2,000 species. The remaining families count together for less than 1500 species.
Asterales
7327329
Boraginales Boraginales is a valid taxonomic name at the rank of order for a group of flowering plants. When recognized, it includes Boraginaceae and closely related asterid families. Boraginales is recognized in neither of two major classification systems, the Cronquist system and the APG III system, but has been recognized in some recent scientific papers. The circumscription of Boraginales is essentially identical to the circumscription of Boraginaceae "sensu" APG. The APG III system takes a broad view of Boraginaceae, including within it the traditionally recognized families Hydrophyllaceae and Lennoaceae based on recent molecular phylogenies that show that Boraginaceae, as traditionally
Boraginales
5286304
comprises less than five hundred species total: many of these are aquatic or semiaquatic plants (see Alismatidae info). The APG II system does not use formal botanical names above the rank of order; it assigns most of the plants involved to the (expanded) order Alismatales, in the clade 'monocots', although the plants in Cronquist's order Triuridales are assigned to quite different placements. Alismatidae Alismatidae is a botanical name at the rank of subclass. Circumscription of the subclass will vary with the taxonomic system being used (there are many such systems); the only requirement being that it includes the family Alismataceae.
Alismatidae
20522173
time provisionally been considered to be closely related. Informal group (taxonomy) In taxonomy, an informal group is not a well defined taxonomic rank. This type of group can be paraphyletic or polyphyletic but is kept for ease, pending new systems of classification. Examples can be found in the classification of gastropods: Opisthobranchia, Sorbeoconcha, Hypsogastropoda and Ptenoglossa are informal groups nearby the level of the order. In human taxonomy, the informal taxonomic rank of race is variously considered equivalent or subordinate to the rank of subspecies. An alliance is also considered an informal grouping of species, genera or tribes to which
Informal group (taxonomy)
15636414
Veillonellaceae and Acidaminococcaceae based on 16S rRNA gene sequence similarity. However, these groupings did not include several members within the Negativicutes that branched outside of the two families. The current taxonomic view is inclusive of these members who have been validly assigned to the families Selenomonadaceae and Sporomusaceae within the emended Selenomonadales order. Molecular markers in the form of conserved signature indels (CSIs) and proteins (CSPs) justify the present taxonomic divisions. These molecular markers are found at each taxonomic rank, and their distribution is in agreement with the observed phylogenetic branching. Many works have implicated that the Negativicutes should be
Negativicutes
17643257
Entomophthoromycota Entomophthoromycota is a fungus division. In 2007, it was placed at the taxonomic rank of subphylum in the most recent revision of the entire fungus kingdom. In 2012, it was raised to the rank of phylum as "Entomophthoromycota" in a scientific paper by Richard A. Humber 2012. Divided into three classes and six families (Ancylistaceae, Basidiobolaceae, Completoriaceae, Entomophthoraceae, Meristacraceae, and Neozygitaceae), it contains over 250 species that are mostly arthropod pathogens or soil- and litter-borne saprobes. Circumscribed by mycologist Richard Humber in 2012, it contains species formerly classified in the division Zygomycota. Humber's reorganization divides the division into three
Entomophthoromycota
1931940
clearly distinguishable taxon below the rank of species; generally, in legislative texts, a term equivalent to cultivar. See also: cultivar and variety (varietas)". A variety will have an appearance distinct from other varieties, but will hybridize freely with those other varieties (if brought into contact). Variety (botany) In botanical nomenclature, variety (abbreviated var.; in ) is a taxonomic rank below that of species and subspecies but above that of form. As such, it gets a three-part infraspecific name. It is sometimes recommended that the subspecies rank should be used to recognize geographic distinctiveness, whereas the variety rank is appropriate if
Variety (botany)
578985
2007 and 2008 paper, "Horabagrus", "Phreatobius", and "Conorhynchos" were not classified under any current catfish families. There is disagreement on the family status of certain groups; for example, Nelson (2006) lists Auchenoglanididae and Heteropneustidae as separate families, while the All Catfish Species Inventory (ACSI) includes them under other families. Also, FishBase and the Integrated Taxonomic Information System lists Parakysidae as a separate family, while this group is included under Akysidae by both Nelson (2006) and ACSI. Many sources do not list the recently revised family Anchariidae. The family Horabagridae, including "Horabagrus", "Pseudeutropius", and "Platytropius", is also not shown by some
Catfish
3845795
aquatic during the larval stage. Some Cecidomyiidae (e.g., the sorghum midge) are significant plant pests. The larvae of some Chironomidae contain haemoglobin and are sometimes referred to as bloodworms. Non-biting midge flies are a common minor nuisance around man-made bodies of water, and are frequently mistaken for mosquitos. Midge Midges are a group of insects that include many kinds of small flies. They are found (seasonally or otherwise) on practically every land area outside permanently arid deserts and the frigid zones. The term "midge" does not define any particular taxonomic group, but includes species in several families of Nematoceran Diptera.
Midge
3845792
Midge Midges are a group of insects that include many kinds of small flies. They are found (seasonally or otherwise) on practically every land area outside permanently arid deserts and the frigid zones. The term "midge" does not define any particular taxonomic group, but includes species in several families of Nematoceran Diptera. Some midges, such as many Phlebotominae (sand fly) and Simuliidae (black fly), are vectors of various diseases. Many others play useful roles as prey items for insectivores, such as various frogs and swallows. Others are important as detritivores, participating in various nutrient cycles. The habits of midges vary
Midge
12188733
the Entomobryomorpha (then called Entomobryoidea) in a group called "Arthropleona", but this has more recently turned out to be paraphyletic. Actually the Entomobryomorpha, the Poduromorpha, and the third springtail lineage – the Symphypleona – are equally distinct from each other. Their treatment at equal taxonomic rank reflects this. Their rank has also varied a bit. When the springtails were still believed to be an order of insects, the "Arthropleona" and the Symphypleona were treated as suborders. Includes fossil families. Superfamily Neanuroidea Superfamily Poduroidea Superfamily Hypogastruroidea Superfamily Gulgastruroidea Superfamily Onychiuroidea Superfamily Isotogastruroidea Poduromorpha The order Poduromorpha is one of the three
Poduromorpha
7327333
Hydrophyllaceae for more than a century after it was placed there by Asa Gray, but it is now known to belong in the order Solanales as sister to Sphenoclea. "Pteleocarpa" was long regarded as an anomaly, and was usually placed in Boraginales, but with considerable doubt. The molecular evidence strongly supports it as sister to Gelsemiaceae, and that family has been expanded to include it. Boraginales Boraginales is a valid taxonomic name at the rank of order for a group of flowering plants. When recognized, it includes Boraginaceae and closely related asterid families. Boraginales is recognized in neither of two
Boraginales
343840
Rosales Rosales is an order of flowering plants. It is sister to a clade consisting of Fagales and Cucurbitales. It contains about 7700 species, distributed into about 260 genera. Rosales comprise nine families, the type family being the rose family, Rosaceae. The largest of these families are Rosaceae (90/2500) and Urticaceae (54/2600). The order Rosales is divided into three clades that have never been assigned a taxonomic rank. The basal clade consists of the family Rosaceae; another clade consists of four families, including Rhamnaceae; and the third clade consists of the four urticalean families. The order Rosales is strongly supported
Rosales
1931938
Variety (botany) In botanical nomenclature, variety (abbreviated var.; in ) is a taxonomic rank below that of species and subspecies but above that of form. As such, it gets a three-part infraspecific name. It is sometimes recommended that the subspecies rank should be used to recognize geographic distinctiveness, whereas the variety rank is appropriate if the taxon is seen throughout the geographic range of the species. The pincushion cactus, "Escobaria vivipara" , is a wide-ranging variable species occurring from Canada to Mexico, and found throughout New Mexico below about . Nine varieties have been described. Where the varieties of the
Variety (botany)
2325757
Dendrology Dendrology (, "dendron", "tree"; and , "-logia", "science of" or "study of") or xylology (, "ksulon", "wood") is the science and study of wooded plants (trees, shrubs, and lianas), specifically, their taxonomic classifications. There is no sharp boundary between plant taxonomy and dendrology; however, woody plants not only belong to many different plant families, but these families may be made up of both woody and non-woody members. Some families include only a few woody species. Dendrology, as a discipline of industrial forestry, tends to focus on identification of economically useful woody plants and their taxonomic interrelationships. As an academic
Dendrology
1741617
the most visible members of Apidae are social, the vast majority of apid bees are solitary, including a number of cleptoparasitic species. The old family Apidae contained four tribes (Apinae: Apini, Euglossini and Bombinae: Bombini, Meliponini) which have been reclassified as tribes of the subfamily Apinae, along with all of the former tribes of Anthophoridae (subfamily Athophorinae) and the former family Ctenoplectridae, which was demoted to tribe status. The trend to move groups down in taxonomic rank has been taken further by a 2005 Brazilian classification that places all existing bee families together under the name "Apidae", but it has
Apidae
87297
"Systema Naturae" in 1758, with the Latin classification translating into the English words "dog wolf". A subspecies is the taxonomic rank below species. When geographically separate populations of a species exhibit recognizable phenotypic differences, biologists may identify these as separate subspecies; a subspecies is a recognized local variant of a species. The 38 subspecies of "Canis lupus" are listed in "Mammal Species of the World" (third edition) that was published in 2005, and in the Catalogue of Life. The nominate subspecies is the Eurasian wolf ("Canis lupus lupus"), also known as the common wolf. The subspecies includes the domestic dog,
Subspecies of Canis lupus
343845
order are used in all different countries in the world. Scientifically it has been proven that the chemicals can be used in both remedies and therapeutic ways. Rosales Rosales is an order of flowering plants. It is sister to a clade consisting of Fagales and Cucurbitales. It contains about 7700 species, distributed into about 260 genera. Rosales comprise nine families, the type family being the rose family, Rosaceae. The largest of these families are Rosaceae (90/2500) and Urticaceae (54/2600). The order Rosales is divided into three clades that have never been assigned a taxonomic rank. The basal clade consists of
Rosales
4938909
fulfill the original intention - a complete index of plant names. Entries at IPNI are designated with the abbreviation "(IK)". Index Kewensis The Index Kewensis (IK), maintained by the Royal Botanic Gardens, Kew, is a publication that aims to register all botanical names for seed plants at the rank of species and genera. It later came to include names of taxonomic families and ranks below that of species. The "Index" is currently maintained as part of the International Plant Names Index in combination with the Gray Herbarium and Australian Plant Name indexes. This database is anticipated to complete the task
Index Kewensis
38776
crown group Aves (alternately Neornithes), which has two subdivisions: the Palaeognathae, which includes the flightless ratites (such as the ostriches) and the weak-flying tinamous, and the extremely diverse Neognathae, containing all other birds. These two subdivisions are often given the rank of superorder, although Livezey and Zusi assigned them "cohort" rank. Depending on the taxonomic viewpoint, the number of known living bird species varies anywhere from 9,800 to 10,050. The discovery of "Vegavis", a late Cretaceous member of the Anatidae, proved that the diversification of modern birds started before the Cenozoic. The affinities of an earlier fossil, the possible galliform
Bird
7032108
prey but causing no harm to humans when bitten. There is not a single or special taxonomic group for venomous snakes that comprise species from different families. This has been interpreted to mean venom in snakes originated more than once as the result of convergent evolution. Around a quarter of all snake species are identified as being venomous. Venomous snakes are often said to be poisonous, but poison and venom are not the same thing. Poisons must be ingested, inhaled or absorbed, while venom must be injected into the body by mechanical means. While unusual, there are a few species
Venomous snake
251245
upon which clades in the order are given the taxonomic rank of family. In the APG III system, 35 families are recognized. Medusagynaceae, Quiinaceae, Peraceae, Malesherbiaceae, Turneraceae, Samydaceae, and Scyphostegiaceae are consolidated into other families. The largest family, by far, is the Euphorbiaceae, with about 6300 species in about 245 genera. In a 2009 study of DNA sequences of 13 genes, 42 families were placed into 16 groups, ranging in size from one to 10 families. Almost nothing is known about the relationships among these 16 groups. Malpighiales and Lamiales are the two large orders whose phylogeny remains mostly unresolved.
Malpighiales
6106730
the term "polecat" is sometimes applied to electric utility linemen. According to the taxonomic theory proposing two subfamilies within Mustelidae, the polecats are classified as: Subfamily Mustelinae A more recent classification based on genetic analysis suggests that Mustelidae should be divided into eight subfamilies, one of which is the Mustelinae. Polecat Polecat is the common name for mammals in the order Carnivora and subfamily Mustelinae. Polecats do not form a single taxonomic rank; the name is applied to several species broadly similar to European polecats, the only species native to the British Isles. In the United States, the term "polecat"
Polecat
7368502
II system does not use formal botanical names above the rank of order; most of the plants involved here are assigned to the clade commelinids in the monocots (its predecessor, the APG system used the clade commelinoids). Commelinidae Commelinidae is a botanical name at the rank of subclass. Circumscription of the subclass will vary with the taxonomic system being used (there are many such systems); the only requirement being that it includes the family Commelinaceae. A well-known system that did use this name is the Cronquist system (1981), but it was also used by the Takhtajan system: In the Takhtajan
Commelinidae
12284718
from Sri Lanka in 2003. Damselflies categorized in to Suborder: Zygoptera; and dragonflies into Suborder: Anisoptera. There are 121 described species within 13 families can be found in Sri Lanka. 59 species from them are endemic. Hubbard and co-workers documented 46 species in 8 families of order Ephemeroptera. Henneman in 2002 recorded 69 species in order Orthoptera. He also collected few specimen of order Phasmatodea around central hills. 66 species of order Blattodea are found, but not taxonomic evidences. Few species of the order Mantodea were studies by Henry in 1931. Clear documentation of the species within Dermaptera can be
Wildlife of Sri Lanka
660057
ranks and under several different names. The APG III system of 2009 recognises a clade called "monocots" but does not assign it to a taxonomic rank. The monocots include about 60,000 species. The largest family in this group (and in the flowering plants as a whole) by number of species are the orchids (family Orchidaceae), with more than 20,000 species. About half as many species belong to the true grasses (Poaceae), which are economically the most important family of monocots. In agriculture the majority of the biomass produced comes from monocots. These include not only major grains (rice, wheat, maize,
Monocotyledon
9934253
which is unusual in having a dome-shaped inflorescence. Meissner retained Brown's subgenera, but demoted them to sectional rank. He then further divided "Eubanksia" into four series, "B." ser. "Abietinae", "B." ser. "Salicinae", "B." ser. "Quercinae" and "B." ser. "Dryandroideae". "B." ser. "Abietinae" contained only (but not all) species with hooked styles. The other three series were heterogeneous. Meissner's taxonomic arrangement of "Banksia" may be summarised as follows: Meissner's arrangement remained current until 1870, when it was superseded by George Bentham's arrangement as published in Volume V of "Flora Australiensis". Section "Isostylis" is now maintained at subgenus level as "Banksia" subg.
Meissner's taxonomic arrangement of Banksia
12981879
grow on rock). Graphidaceae The Graphidaceae are a family of funghi in the order Ostropales. The current circumscription of Graphidaceae includes all taxa in the formerly independent families Thelotremataceae, Gomphillaceae, and Asterothyriaceae. Graphidaceae is believed to be the most speciose family of lichenized fungi; over 2000 species are included in the current taxonomic concept of the family, and there are likely several hundred more that are undiscovered or undescribed. The vast majority of these species are restricted to the tropics. Most Graphidaceae species are epiphytic (i.e. they grow only on plants). Species in several genera (Diploschistes, Gymnographopsis, and Rendonographa) are
Graphidaceae
12981878
Graphidaceae The Graphidaceae are a family of funghi in the order Ostropales. The current circumscription of Graphidaceae includes all taxa in the formerly independent families Thelotremataceae, Gomphillaceae, and Asterothyriaceae. Graphidaceae is believed to be the most speciose family of lichenized fungi; over 2000 species are included in the current taxonomic concept of the family, and there are likely several hundred more that are undiscovered or undescribed. The vast majority of these species are restricted to the tropics. Most Graphidaceae species are epiphytic (i.e. they grow only on plants). Species in several genera (Diploschistes, Gymnographopsis, and Rendonographa) are saxicolous (i.e. they
Graphidaceae
7101606
4,225 new species, 742 new genera, 28 new families, and 12 orders. Chamberlin's taxonomic publications continued to appear until at least 1966. Chamberlin ranks among the most prolific arachnologists in history. In a 2013 survey of the most prolific spider systematists, Chamberlin ranked fifth in total number of described species (1,475) and eighth in number of species that were still valid (984), i.e. not taxonomic synonyms of previously described species. At the University of Utah Chamberlin co-authored several works with his students Wilton Ivie and Willis J. Gertsch, who would both go on to become notable spider scientists: the "famous
Ralph Vary Chamberlin
3494427
Sorbeoconcha Sorbeoconcha is a taxonomic clade of snails, i.e. gastropods, mainly marine species with gills and opercula, within the clade Caenogastropoda. The taxon Sorbeoconcha was named by Winston Ponder and David R. Lindberg in 1997. According to the older taxonomy by Ponder and Lindberg the suborders within the order Sorbeoconcha are: In the taxonomy by Bouchet & Rocroi (2005), the clade Sorbeoconcha was declared a taxon of unspecified rank, within the clade Caenogastropoda. It comprises the superfamily Cerithioidea, the superfamily Campaniloidea, the informal group Ptenoglossa and the clade Neogastropoda. The following extinct families were not allocated to a superfamily: The
Sorbeoconcha
1557843
some consider it a subspecies of a larger herring gull species and therefore call it "Larus argentatus smithsonianus", while others consider it a full species and therefore call it "Larus smithsonianus" (and the user of the notation is not taking a position). A subspecies is a taxonomic rank below species – the only recognized rank in the zoological code, and one of three main ranks below species in the botanical code. When geographically separate populations of a species exhibit recognizable phenotypic differences, biologists may identify these as separate subspecies; a subspecies is a recognized local variant of a species. Botanists
Subspecies
2042171
Scallop Scallop () is a common name that is primarily applied to any one of numerous species of saltwater clams or marine bivalve mollusks in the taxonomic family Pectinidae, the scallops. However, the common name "scallop" is also sometimes applied to species in other closely related families within the superfamily Pectinoidea, which also includes the thorny oysters. Scallops are a cosmopolitan family of bivalves which are found in all of the world's oceans, although never in fresh water. They are one of very few groups of bivalves to be primarily "free-living", with many species capable of rapidly swimming short distances
Scallop
9639190
always producing the same species, and this was fixed and permanent, though considerable variation was possible within a species. Carolus Linnaeus (1707–1778) formalized the taxonomic rank of species, and devised the two part naming system of binomial nomenclature that we use today. However, this did not prevent disagreements on the best way to identify species. The history of definitions of the term "species" reveal that the seeds of the modern species debate were alive and growing long before Darwin. "The traditional view, which was developed by Cain, Mayr and Hull in the mid-twentieth century, claims that until the ‘Origin of
Species problem
2533244
and are not defined as subspecies in their own right) The known sub-species within the lineage 'A' are: The known sub-species within the lineage 'C' are: The known sub-species within the lineage 'M' are: The known sub-species within the lineage 'O' are: The known sub-species within the lineage 'Y') are: Honey bee race Within biological taxonomy, a Honey bee race would be an informal rank in the taxonomic hierarchy, below the level of subspecies. It has been used as a higher rank than strain, with several strains making up one race. Therefore a strain (within the Honey bee context) is
Honey bee race
6081147
Nomenclature codes Nomenclature codes or codes of nomenclature are the various rulebooks that govern biological taxonomic nomenclature, each in their own broad field of organisms. To an end-user who only deals with names of species, with some awareness that species are assignable to families, it may not be noticeable that there is more than one code, but beyond this basic level these are rather different in the way they work. The successful introduction of two-part names for species by Linnaeus was the start for an ever-expanding system of nomenclature. With all naturalists worldwide adopting this approach to thinking up names
Nomenclature codes
1409335
Adelgoidea, the Aphidoidea and the Phylloxeroidea. Some authors use a single superfamily Aphidoidea within which the Phylloxeridae and Adelgidae are also included while others have Aphidoidea with a sister superfamily Phylloxeroidea within which the Adelgidae and Phylloxeridae are placed. Early 21st-century reclassifications substantially rearranged the families within Aphidoidea: some old families were reduced to subfamily rank ("e.g.", Eriosomatidae), and many old subfamilies were elevated to family rank. The most recent authoritative classifications have three superfamilies Adelgoidea, Phylloxeroidea and Aphidoidea. The Aphidoidea includes a single large family Aphididae that includes all the ~5000 extant species. Aphids, adelgids, and phylloxerids are very
Aphid
13095565
Sigmurethra Sigmurethra is a taxonomic category of air-breathing land snails and slugs, terrestrial pulmonate gastropod molluscs. This is an informal group which includes the majority of land snails and slugs. The two strong synapomorphies of Sigmurethra are a long pedal gland placed beneath a membrane and retractile tentacles. Several families in this group contain species of snails and slugs that create love darts. Sigmurethra are known from the Cretaceous to the Recent periods. In the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005, Sigmurethra is an "Informal Group", a subsection of the Stylommatophora. It consists of the following families:
Sigmurethra
2042221
Benjamin Britten, who had a long association with the town. Scallop Scallop () is a common name that is primarily applied to any one of numerous species of saltwater clams or marine bivalve mollusks in the taxonomic family Pectinidae, the scallops. However, the common name "scallop" is also sometimes applied to species in other closely related families within the superfamily Pectinoidea, which also includes the thorny oysters. Scallops are a cosmopolitan family of bivalves which are found in all of the world's oceans, although never in fresh water. They are one of very few groups of bivalves to be primarily
Scallop
14331859
(6 n.spp.) and Heteroderid (4 n.spp.) families and he also described a few new species in other groups, to a total of over 87 new species. In addition, he described three new genera, "Hirschmanniella" (Luc & Goodey, 1962), that includes some of the most destructive pests of rice, "Hylonema" Luc, Taylor & Cadet, 1978, and "Senegalonema" Germani, Luc & Baldwin, 1983. In spite of this large number of new taxa, he considered himself to be a "lumper" and spent considerable energy fighting against the "taxonomic inflation" created by excessive splitting of taxa. In 1987, he led a team (including Armand
Michel Luc
2177706
Jurassic. The rank of "Theria" may vary depending on the classification system used. The textbook classification system by Vaughan et al. (2000) gives the following: In the above system Theria is a subclass. Alternatively, in the system proposed by McKenna and Bell (1997) it is ranked as a supercohort under the subclass Theriiformes: Another classification proposed by Luo et al. (2002) does not assign any rank to the taxonomic levels, but uses a purely cladistic system instead. Theria Theria (; Greek: , wild beast) is a subclass of mammals amongst the Theriiformes (the sister taxon to Yinotheria). Theria includes the
Theria
10427724
them to the taxonomic rank of family as Icacinaceae. Philippe van Tieghem realized that the family Icacinaceae, as circumscribed by Miers, consisted of groups that were only distantly related, and in 1897, he divided it into seven families. Van Tieghem's treatment in some ways anticipated the results of 21st century phylogenetic studies, in particular, by his establishment of the families Emmotaceae and Leptaulaceae. His division of Icacinaceae into smaller families was not accepted and other authors continued to define Icacinaceae in the broad sense, known as Icacinaceae sensu lato. In 1942, Hermann Sleumer defined Icacinaceae broadly in his coverage of
Icacinaceae
5092351
and the necessary reference point for any taxonomic or local flora study. The infrageneric classification presented by Pax & Hoffmann is based on that from Müller Argoviensis, except in the rank of subgeneric taxa. Moreover, they use series and section categories in an opposite way to Muller’s: the series are described as higher ranked than sections are. So they divide "Acalypha" into three subgenera: "Linostachys", "Androcephala" and "Euacalypha". The "Androcephala" subgenus, single-typed, includes a species from Madagascar with pedicellate female flowers and capituliform male inflorescences. They divide "Linostachys" subgenus into three sections, and "Euacalypha" subgenus into 8 series and 39
Acalypha
13097660
Species In biology, a species is the basic unit of classification and a taxonomic rank, as well as a unit of biodiversity, but it has proven difficult to find a satisfactory definition. Scientists and conservationists need a species definition which allows them to work, regardless of the theoretical difficulties. If as Carl Linnaeus thought, species were fixed and clearly distinct from one another, there would be no problem, but evolutionary processes cause species to change continually, and to grade into one another. A species is often defined as the largest group of organisms in which any two individuals of the
Species
2825788
specimens there is no requirement for a "typical" individual to be used. Genera and families, particularly those established by early taxonomists, tend to be named after species that are more "typical" for them, but here too this is not always the case and due to changes in systematics "cannot" be. Hence, the term name-bearing type or onomatophore is sometimes used, to denote the fact that biological types do not define "typical" individuals or taxa, but rather fix a scientific name to a specific operational taxonomic unit. Type specimens are theoretically even allowed to be aberrant or deformed individuals or color
Type (biology)
7367332
clade monocots. In other words, by today's standards Cronquist's subclass was not a "good" group. Arecidae Arecidae is a botanical name at the rank of subclass. Circumscription of the subclass will vary with the taxonomic system being used (there are many such systems); the only requirement being that it includes the family Arecaceae. The Takhtajan system used this name for a subclass in the class Liliopsida (=monocotyledons). The Cronquist system (1981) used this name for a subclass in the class Liliopsida (=monocotyledons), with the circumscription: The APG II system does not use formal botanical names above the rank of order;
Arecidae
13691424
subtribe Catocalina. This species is probably related to other North American willow – and cottonwood – feeding "Catocala". If so, it is one of the rather few species of this radiation that ranges east of the Rocky Mountains. In the past, the name "Catocala aspasia" has often been used for this species, but actually it seems to refer to the rather similar "C. electilis". Many taxa described as distinct species or subspecies have recently been merged with "C. junctura" and are considered mere forms without taxonomic rank; the alternate vernacular name "Stretch's Underwing" in fact refers to one of these,
Catocala junctura
10590143
Stylidium sect. Debilia "Stylidium" section Debilia is a taxonomic rank under "Stylidium" subgenus "Tolypangium". In his 1908 monograph on the family Stylidiaceae, Johannes Mildbraed had established this section as "Debiles". In 1999, A.R. Bean published a taxonomic revision of several sections in subgenus "Tolypangium" in which he renamed the section from "Debiles" to "Debilia". Species in this section are distinguished by their cylindrical, unthickened rootstocks. They generally have oblanceolate, elliptical, or obovate leaves that are in terminal rosettes or cauline in growth habit. Their flower petals are all free and entire. This section contains ten species in total that are
Stylidium sect. Debilia