Misplaced Pages

Hexaplex

Article snapshot taken from Wikipedia with creative commons attribution-sharealike license. Give it a read and then ask your questions in the chat. We can research this topic together.

Genus ( / ˈ dʒ iː n ə s / ; pl. : genera / ˈ dʒ ɛ n ər ə / ) is a taxonomic rank above species and below family as used in the biological classification of living and fossil organisms as well as viruses . In binomial nomenclature , the genus name forms the first part of the binomial species name for each species within the genus.

#28971

42-538: Hexaplex is a genus of medium-sized to large sea snails , marine gastropod mollusks in the subfamily muracinae of the family Muricidae , the murex shells or rock snails. This genus is known in the fossil record from the Paleocene to the Quaternary period (age range: from 61.7 to 0.012 million years ago.). Fossil shells within this genus have been found all over the world. This genus includes shells in

84-557: A species : see Botanical name and Specific name (zoology) . The rules for the scientific names of organisms are laid down in the nomenclature codes , which allow each species a single unique name that, for animals (including protists ), plants (also including algae and fungi ) and prokaryotes ( bacteria and archaea ), is Latin and binomial in form; this contrasts with common or vernacular names , which are non-standardized, can be non-unique, and typically also vary by country and language of usage. Except for viruses ,

126-651: A later homonym of a validly published name is a nomen illegitimum or nom. illeg. ; for a full list refer to the International Code of Nomenclature for algae, fungi, and plants and the work cited above by Hawksworth, 2010. In place of the "valid taxon" in zoology, the nearest equivalent in botany is " correct name " or "current name" which can, again, differ or change with alternative taxonomic treatments or new information that results in previously accepted genera being combined or split. Prokaryote and virus codes of nomenclature also exist which serve as

168-628: A long time and redescribed as new by a range of subsequent workers, or if a range of genera previously considered separate taxa have subsequently been consolidated into one. For example, the World Register of Marine Species presently lists 8 genus-level synonyms for the sperm whale genus Physeter Linnaeus, 1758, and 13 for the bivalve genus Pecten O.F. Müller, 1776. Within the same kingdom, one generic name can apply to one genus only. However, many names have been assigned (usually unintentionally) to two or more different genera. For example,

210-694: A name, but not the connecting term. For example: The recommended abbreviations for ranks below species are: Although the connecting terms mentioned above are the recommended ones, the ICN allows for other connecting terms in validly published infraspecific taxa. It specifically mentions that Greek letters α, β, γ, etc. can be used in this way in the original document and further ranks may be added without limit. Names that use these connecting terms are now deprecated (though still legal), but they have an importance because they can be basionyms of current species. The commonest cases use "β" and "b"; examples mentioned in

252-510: A plant should be given a particular infraspecific name can then be decided by comparing it to the type. There is no requirement for a species to be divided into infraspecific taxa, of whatever rank; in other words, a species does not have to have subspecies, varieties, forms, etc. However, if infraspecific ranks are created, then the name of the type of the species must repeat the specific epithet as its infraspecific epithet. The type acquires this name automatically as soon as any infraspecific rank

294-407: A proposed infraspecific name to be legitimate it must be in accordance with all the rules of the ICN. Only some of the main points are described here. A key concept in botanical names is that of a type . In many cases the type will be a particular preserved specimen stored in a herbarium , although there are other kinds of type. Like other names, an infraspecific name is attached to a type. Whether

336-409: A reference for designating currently accepted genus names as opposed to others which may be either reduced to synonymy, or, in the case of prokaryotes, relegated to a status of "names without standing in prokaryotic nomenclature". An available (zoological) or validly published (botanical) name that has been historically applied to a genus but is not regarded as the accepted (current/valid) name for

378-427: A taxon; however, the names published in suppressed works are made unavailable via the relevant Opinion dealing with the work in question. In botany, similar concepts exist but with different labels. The botanical equivalent of zoology's "available name" is a validly published name . An invalidly published name is a nomen invalidum or nom. inval. ; a rejected name is a nomen rejiciendum or nom. rej. ;

420-455: A total of c. 520,000 published names (including synonyms) as at end 2019, increasing at some 2,500 published generic names per year. "Official" registers of taxon names at all ranks, including genera, exist for a few groups only such as viruses and prokaryotes, while for others there are compendia with no "official" standing such as Index Fungorum for fungi, Index Nominum Algarum and AlgaeBase for algae, Index Nominum Genericorum and

462-490: Is created. As an example, consider Poa secunda J.Presl , whose type specimen is in the Wisconsin State Herbarium. The same epithet can be used again within a species, at whatever level, only if the names with the re-used epithet are attached to the same type. Thus there can be a form called Poa secunda f. juncifolia as well as the subspecies Poa secunda subsp. juncifolia if, and only if,

SECTION 10

#1732771987029

504-612: Is discouraged by both the International Code of Zoological Nomenclature and the International Code of Nomenclature for algae, fungi, and plants , there are some five thousand such names in use in more than one kingdom. For instance, A list of generic homonyms (with their authorities), including both available (validly published) and selected unavailable names, has been compiled by the Interim Register of Marine and Nonmarine Genera (IRMNG). The type genus forms

546-453: Is required as there is only one rank below species, the subspecies . The Prokaryotic Code was split from the ICN in 1975. This nomenclature only governs one infraspecific rank, the subspecies, but allows a number of infrasubspecific subdivisions to be used. The authorship is to be specified in the form " Bacillus subtilis subsp. spizizenii Nakamura et al. 1999.", i.e. with only the infraspecific author. The ICN does not regulate

588-460: Is somewhat arbitrary. Although all species within a genus are supposed to be "similar", there are no objective criteria for grouping species into genera. There is much debate among zoologists about whether enormous, species-rich genera should be maintained, as it is extremely difficult to come up with identification keys or even character sets that distinguish all species. Hence, many taxonomists argue in favor of breaking down large genera. For instance,

630-474: Is the type species , and the generic name is permanently associated with the type specimen of its type species. Should the specimen turn out to be assignable to another genus, the generic name linked to it becomes a junior synonym and the remaining taxa in the former genus need to be reassessed. In zoological usage, taxonomic names, including those of genera, are classified as "available" or "unavailable". Available names are those published in accordance with

672-426: Is the legitimate one and the other must be changed. When indicating authors for infraspecific names, it is possible to show either just the author(s) of the final, infraspecific epithet, or the authors of both the specific and the infraspecific epithets. Examples: In zoological nomenclature , names of taxa below species rank are formed somewhat differently, using a trinomen or 'trinomial name'. No connecting term

714-464: The International Code of Nomenclature for algae, fungi, and plants (ICN). As specified by the ICN, the name of an infraspecific taxon is a combination of the name of a species and an infraspecific epithet , separated by a connecting term that denotes the rank of the taxon. An example of an infraspecific name is Astrophytum myriostigma subvar.  glabrum , the name of a subvariety of the species Astrophytum myriostigma (bishop's hat cactus). In

756-621: The International Code of Zoological Nomenclature ; the earliest such name for any taxon (for example, a genus) should then be selected as the " valid " (i.e., current or accepted) name for the taxon in question. Consequently, there will be more available names than valid names at any point in time; which names are currently in use depending on the judgement of taxonomists in either combining taxa described under multiple names, or splitting taxa which may bring available names previously treated as synonyms back into use. "Unavailable" names in zoology comprise names that either were not published according to

798-824: The International Plant Names Index for plants in general, and ferns through angiosperms, respectively, and Nomenclator Zoologicus and the Index to Organism Names for zoological names. Totals for both "all names" and estimates for "accepted names" as held in the Interim Register of Marine and Nonmarine Genera (IRMNG) are broken down further in the publication by Rees et al., 2020 cited above. The accepted names estimates are as follows, broken down by kingdom: The cited ranges of uncertainty arise because IRMNG lists "uncertain" names (not researched therein) in addition to known "accepted" names;

840-404: The platypus belongs to the genus Ornithorhynchus although George Shaw named it Platypus in 1799 (these two names are thus synonyms ) . However, the name Platypus had already been given to a group of ambrosia beetles by Johann Friedrich Wilhelm Herbst in 1793. A name that means two different things is a homonym . Since beetles and platypuses are both members of the kingdom Animalia,

882-473: The French botanist Joseph Pitton de Tournefort (1656–1708) is considered "the founder of the modern concept of genera". The scientific name (or the scientific epithet) of a genus is also called the generic name ; in modern style guides and science, it is always capitalised. It plays a fundamental role in binomial nomenclature , the system of naming organisms , where it is combined with the scientific name of

SECTION 20

#1732771987029

924-496: The ICN are Cynoglossum cheirifolium β Anchusa ( lanata ) and Polyporus fomentarius β applanatus whilst other examples (coming from the fungus database Index Fungorum ) are Agaricus plexipes b fuliginaria and Peziza capula ß cernua . The ICN allows the possibility that a validly published name could have no defined rank and uses "[unranked]" as the connecting term in such cases. Like specific epithets, infraspecific epithets cannot be used in isolation as names. Thus

966-442: The base for higher taxonomic ranks, such as the family name Canidae ("Canids") based on Canis . However, this does not typically ascend more than one or two levels: the order to which dogs and wolves belong is Carnivora ("Carnivores"). The numbers of either accepted, or all published genus names is not known precisely; Rees et al., 2020 estimate that approximately 310,000 accepted names (valid taxa) may exist, out of

1008-401: The context makes the species clear. The variety cannot be referred to as just macranthum . Sometimes more than three parts will be given; strictly speaking, this is not a name, but a classification . The ICN gives the example of Saxifraga aizoon var. aizoon subvar. brevifolia f. multicaulis subf. surculosa ; the name of the subform would be Saxifraga aizoon subf. surculosa . For

1050-603: The family Muricidae that are solid and globose. They contain five to eight varices that are more or less foliaceous . Species within the genus Hexaplex include : Extinct species within the genus Hexaplex include: This Muricinae -related article is a stub . You can help Misplaced Pages by expanding it . Genus The composition of a genus is determined by taxonomists . The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including

1092-446: The form "author, year" in zoology, and "standard abbreviated author name" in botany. Thus in the examples above, the genus Canis would be cited in full as " Canis Linnaeus, 1758" (zoological usage), while Hibiscus , also first established by Linnaeus but in 1753, is simply " Hibiscus L." (botanical usage). Each genus should have a designated type , although in practice there is a backlog of older names without one. In zoology, this

1134-737: The generic name (or its abbreviated form) still forms the leading portion of the scientific name, for example, Canis lupus lupus for the Eurasian wolf subspecies, or as a botanical example, Hibiscus arnottianus ssp. immaculatus . Also, as visible in the above examples, the Latinised portions of the scientific names of genera and their included species (and infraspecies, where applicable) are, by convention, written in italics . The scientific names of virus species are descriptive, not binomial in form, and may or may not incorporate an indication of their containing genus; for example,

1176-432: The idea that a newly defined genus should fulfill these three criteria to be descriptively useful: Moreover, genera should be composed of phylogenetic units of the same kind as other (analogous) genera. The term "genus" comes from Latin genus , a noun form cognate with gignere ('to bear; to give birth to'). The Swedish taxonomist Carl Linnaeus popularized its use in his 1753 Species Plantarum , but

1218-633: The largest component, with 23,236 ± 5,379 accepted genus names, of which 20,845 ± 4,494 are angiosperms (superclass Angiospermae). By comparison, the 2018 annual edition of the Catalogue of Life (estimated >90% complete, for extant species in the main) contains currently 175,363 "accepted" genus names for 1,744,204 living and 59,284 extinct species, also including genus names only (no species) for some groups. The number of species in genera varies considerably among taxonomic groups. For instance, among (non-avian) reptiles , which have about 1180 genera,

1260-411: The lizard genus Anolis has been suggested to be broken down into 8 or so different genera which would bring its ~400 species to smaller, more manageable subsets. Infraspecific name In botany , an infraspecific name is the scientific name for any taxon below the rank of species , i.e. an infraspecific taxon or infraspecies . The scientific names of botanical taxa are regulated by

1302-403: The most (>300) have only 1 species, ~360 have between 2 and 4 species, 260 have 5–10 species, ~200 have 11–50 species, and only 27 genera have more than 50 species. However, some insect genera such as the bee genera Lasioglossum and Andrena have over 1000 species each. The largest flowering plant genus, Astragalus , contains over 3,000 species. Which species are assigned to a genus

Hexaplex - Misplaced Pages Continue

1344-428: The name could not be used for both. Johann Friedrich Blumenbach published the replacement name Ornithorhynchus in 1800. However, a genus in one kingdom is allowed to bear a scientific name that is in use as a generic name (or the name of a taxon in another rank) in a kingdom that is governed by a different nomenclature code. Names with the same form but applying to different taxa are called "homonyms". Although this

1386-434: The name of a particular species of Acanthocalycium is Acanthocalycium klimpelianum , which can be abbreviated to A. klimpelianum where the context makes the genus clear. The species cannot be referred to as just klimpelianum . In the same way, the name of a particular variety of Acanthocalycium klimpelianum is Acanthocalycium klimpelianum var. macranthum , which can be abbreviated to A. k. var. macranthum where

1428-408: The names of cultivated plants, of cultivars , i.e. plants specifically created for use in agriculture or horticulture. Such names are regulated by the International Code of Nomenclature for Cultivated Plants (ICNCP). Although logically below the rank of species (and hence "infraspecific"), a cultivar name may be attached to any scientific name at the genus level or below. The minimum requirement

1470-416: The previous example, glabrum is the infraspecific epithet. Names below the rank of species of cultivated kinds of plants and of animals are regulated by different codes of nomenclature and are formed somewhat differently. Article 24 of the ICN describes how infraspecific names are constructed. The order of the three parts of an infraspecific name is: It is customary to italicize all three parts of such

1512-541: The provisions of the ICZN Code, e.g., incorrect original or subsequent spellings, names published only in a thesis, and generic names published after 1930 with no type species indicated. According to "Glossary" section of the zoological Code, suppressed names (per published "Opinions" of the International Commission of Zoological Nomenclature) remain available but cannot be used as the valid name for

1554-497: The specific name particular to the wolf. A botanical example would be Hibiscus arnottianus , a particular species of the genus Hibiscus native to Hawaii. The specific name is written in lower-case and may be followed by subspecies names in zoology or a variety of infraspecific names in botany . When the generic name is already known from context, it may be shortened to its initial letter, for example, C. lupus in place of Canis lupus . Where species are further subdivided,

1596-412: The standard format for a species name comprises the generic name, indicating the genus to which the species belongs, followed by the specific epithet, which (within that genus) is unique to the species. For example, the gray wolf 's scientific name is Canis lupus , with Canis ( Latin for 'dog') being the generic name shared by the wolf's close relatives and lupus (Latin for 'wolf') being

1638-403: The taxon is termed a synonym ; some authors also include unavailable names in lists of synonyms as well as available names, such as misspellings, names previously published without fulfilling all of the requirements of the relevant nomenclatural code, and rejected or suppressed names. A particular genus name may have zero to many synonyms, the latter case generally if the genus has been known for

1680-407: The type specimen of Poa secunda f. juncifolia is the same as the type specimen of Poa secunda subsp. juncifolia (in other words, if there is a single type specimen whose classification is Poa secunda subsp. juncifolia f. juncifolia ). If two infraspecific taxa which have different types are accidentally given the same epithet, then a homonym has been created. The earliest published name

1722-576: The values quoted are the mean of "accepted" names alone (all "uncertain" names treated as unaccepted) and "accepted + uncertain" names (all "uncertain" names treated as accepted), with the associated range of uncertainty indicating these two extremes. Within Animalia, the largest phylum is Arthropoda , with 151,697 ± 33,160 accepted genus names, of which 114,387 ± 27,654 are insects (class Insecta). Within Plantae, Tracheophyta (vascular plants) make up

Hexaplex - Misplaced Pages Continue

1764-429: The virus species " Salmonid herpesvirus 1 ", " Salmonid herpesvirus 2 " and " Salmonid herpesvirus 3 " are all within the genus Salmonivirus ; however, the genus to which the species with the formal names " Everglades virus " and " Ross River virus " are assigned is Alphavirus . As with scientific names at other ranks, in all groups other than viruses, names of genera may be cited with their authorities, typically in

#28971