ICBN.pdf

ICBN.pdf

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  BOTANY 25/11/2021 TAXONOMY GFGCYELAHANKA P B Mallikharjuna,PhD Page 1 PLANT NOMENCLATURE Plant nomenclature is an important aspect of Taxonomy. The naming of plants based on certain rules is proposed by the International Botanical Society(IBS) over a period of time is called Plant Nomenclature. These names are usually termed as the botanical names or the scientific names. These are evolved as the Binomials from the Polynomials and the Vernaculars through the ages. BINOMIAL NOMENCLATURE The method of giving scientific names to plants, animals and microbes with the name consisting of two parts is binomial nomenclature (ICBN, Art.23.1) Therefore, the scientific names of organisms are always binomials. Ex. 1. Mangifera indica (plant) 2. Homo sapiens (Human being) 3. Mus musculus (animal, mouse) & 4. Escherichia coli (microbe, bacterium) Naming the organisms become essential mainly for three reasons  To remember the particular organism, we studied  To communicate the same with the others, and  To maintain the scientific documentation. Giving names to organisms is in practice since time immemorial. However, the names used in earlier days are vernacular names in local languages and such names have many defects. For example; 1. They do not remain same throughout the world, 2. They tend to change from place to place and from language to language, 3. In some instances, a common name is applied to different plants and the same plant may be called by different names, and 4. Common names are not available to all kinds of plants. Therefore, there was a necessity to give scientific names. However, the first introduced scientific names were Polynomials. These were lengthier, descriptive and difficult to remember. For example, Gravellia robusta grandiflora australiana. Later the binomial system is proposed, where the name is consisted only of two parts. The first part of the name is the genus name and the second part is the species name or specific epithet. This binomial system was actually proposed for the first time by “Casper Bauhin”( 1623), but he did not make its application compulsory. Later, it was Linnaeus (1753), a Swedish botanist, who adopted the binomial nomenclature in his “Species plantarum, 1753”, and hence the credit gone to Linnaeus. Therefore, 1st May
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  BOTANY 25/11/2021 TAXONOMY GFGCYELAHANKA P B Mallikharjuna,PhD Page 2 1753 is regarded as the beginning date of the scientific names of all living beings including plants. Latin is the chosen language for scientific names. Certain rules are to be followed while giving the binomials. The first letter of the genus should be capital and the first letter of the species should be a small letter. For example, Mangifera indica & Cocos nucifera etc. Whenever, these names are hand- written or type written they are to be underlined. The names should be in Latin language or if the names are derived from any other source, they are to be Latinised. The genus name always be a noun, the species name will be an adjective, and hence it usually reveals of a character or home of the place. For example, Solanum nigrum (nigrum-black), Mangifera indica (Indica-India). The scientific names usually followed by the name of the author in abbreviation form, who validly published it for the first time. Example: Mangifera indica L. (L-Linnaeus). ICBN International code of botanical nomenclature (ICBN) or the Code is the premier constituent body of the International Botanical Society/Congress. Its main objective is to look after the plant nomenclature of both extant and extinct taxa. The first code was held in Paris, France (1867) under the guidance of A.P. de Condolle. The basis for the code has been drawn from de Condolle's “Theorie Elementiare de la Botanique” and also from the Linnaeus’ “Critica Botanica”, “Fundamenta Botanica” and “Philosophia Botanica”. Since then for every 6 years, the International Botanical Congress (IBC) meeting was held to discuss the various aspects of nomenclature and publishing its proceedings as the Code. The latest edition of Code i.e., 19th edition was held in Shenzen, China (2017) recently and which supersedes all previous editions. The Code/ICBN is mainly consisting of the preamble and three divisions as follows THE PREAMBLE Botany requires a precise and simple system of nomenclature used by Botanists all over the world.
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  BOTANY 25/11/2021 TAXONOMY GFGCYELAHANKA P B Mallikharjuna,PhD Page 3 AIM OF THE CODE: 1. It aims at the provisions of a stable method of naming taxonomic groups, avoiding or rejecting the use of names, which may cause error or ambiguity. 2. Further, it aims at the avoidance of the useless creation of new names. Division I - Principles: these will form the basis of the system of botanical nomenclature and has six Principles, namely,  Principle I: Botanical nomenclature is independent of zoological and bacteriological nomenclatures. Further, the code applies equally to names of taxonomic groups treated as plants whether or not these groups were originally so treated.  Principle II: The application of names of taxonomic groups is determined by means of nomenclature types.  Principle III: The nomenclature of a taxonomic group is based upon the priority of publication.  Principle IV: Each taxonomic group with a particular circumscription, position and rank can bear only one correct name, the earliest that is in accordance with the rules, except in specified cases.  Principle V: Scientific names of taxonomic groups are treated as Latin regardless of their derivation.  Principle VI: The rules of nomenclature are retroactive unless expressly limited. Division II - Rules and Recommendations: The detail provisions of the code are divided into Rules in the form of Articles (62) and which are binding. The main objective of rules is to put the nomenclature of the past into order and to provide the same for the future. Whereas, Recommendations are subsidiary points and which are non-binding but to be preferred. The main objective is to bring about greater uniformity and clarity especially in future nomenclature. This division included 7 Chapters, 16 Sections and 62 Articles. o Chapter I deals with taxa and their ranks (Art 1-5) o Chapter II deals with typification (Art. 6-10) and rule of priority (Art. 11-15) o Chapter III deals with nomenclature of taxa according to their ranks (Art.16-28) o Chapter IV deals with Effective and Valid publication (Art. 29-50) o Chapter V deals with rejection of names (Art. 51-58) o Chapter VI deals with the names of fungi with pleomorphic life cycle (Art 59), & o Chapter VII deals with the Orthography and gender of names (Art: 60-62) Division III: Includes provisions regulating the governance of the code. It has five appendices namely;  Appendix I: names of hybrids
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  BOTANY 25/11/2021 TAXONOMY GFGCYELAHANKA P B Mallikharjuna,PhD Page 4  Appendix IIA/B: Nomina familiarum conservanda (Family names conserved)  Appendix IIIA/B: Nomina generica/specifica conservanda et rejicienda (The rejected names of the genera/species are conserved)  Appendix IV: Nomina utique rejicienda (rejected in favour of a particular conserved name, and combinations based on a suppressed name)  Appendix V: opera utique oppressa (Rejection of names) ----------------------------------------------------------------------------------------------------------------------- RULE OF PRIORITY According to the Code /ICBN rule,” Each family or taxon of lower rank with a particular circumscription, position and rank can bear only one correct name. And, it is the earliest legitimate one which is validly published with the same rank (Art 11). Further, the name of a taxon has no status under this code unless it is validly published (Art 12)”. The date of valid publication is 1st May 1753 of Linnaeus ‘Species plantarum’. For instance, when there are several names for a taxon, the earliest name, which is validly published, is regarded as the correct name. Thus, the rule of priority gives stability to the plant nomenclature. Ex: Cleome gynandra Linn (1753) Cleome pentaphylla Linn (1762) Gynandropsis pentaphylla DC (1824) The above three names are existing for a single taxon. Of these, the earliest one i.e., Cleome gynandra is valid and legitimate name according to the the priority. While the other two are synonyms and these are conserved in the appendix IIIB of the Code ( Nomina specifica conservanda et rejicienda). Finally, the application of both conserved and rejected names, are determined by the nomenclature type (Art 14). Effective and Valid publication According to the Code/ICBN, the author to make it, as a correct or legitimate name must effectively and validly published the scientific name of a given taxon. In general, effective publication deals with standards applicable to the media. In which the names are published and not to the names themselves (Article 29). Whereas, valid publication deals with standards applicable to the names themselves (Article 32 – 45). There are four general criteria for publication of a name, 1. The name must be effectively published. That means it must be published in a journal commonly available to botanists such as Rheedea (at national level) or TAXON or Systematic Botany (at international level).
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  BOTANY 25/11/2021 TAXONOMY GFGCYELAHANKA P B Mallikharjuna,PhD Page 5 2. The name must be published in the correct form, i.e., properly Latinised, with rank indicated (Ex. as “sp.nov” or “gen.nov”). Such a name in correct form is known as the admissible name. 3. The name must be published with a Latin description or diagnosis or with a reference to such. The diagnosis maybe a brief account. For instance, listing how the new taxon is different from a similar, related taxon. 4. A nomenclatural type must be indicated. Finally, the term “PROTOLOGUE” is “everything associated with a name at its valid publication i.e., description or diagnosis, illustrations, references, synonyms, geographical data, citation of specimens, discussion and comments”. A full citation of a scientific name may include the authorship and the journal, volume, page numbers and data of publication. For ex: A complete citation for the new species (sp.nov). Cited as: Perityle vigilans Spellenb & A. Powell, Syst. Bot.15: 252.1990. TYPIFICATION (Type Method) According to the Code/ICBN (Article 7-10), the application of names to taxonomic groups is governed by nomenclatural types. This rule previously applicable to the rank of family or below. However, now it is extended to the names of taxa of higher ranks when the names are ultimately based on generic names. Nomenclature type: it is the representative element of a taxon. When any author publishes the account of species, the original plant on which the description is based, is deposited in any standard Herbarium (like Kew Herbarium). This type specimen becomes the nomenclatural type of that specimen and is associated ever with the specific name given on its basis. Type specimen: is the one that is ultimately associated with the name of a taxon. The type for a genus is a species, for a family it is a genus, and for an order, it is a family. Examples:  Ex: Rosa indica (Species) Rosa (Genus) Rosaceae (Family)  Rosales (Order)  Magnolia grandiflora (Species)  Magnolia (Genus)Magnoliaceae (Family)Magnoliales (Order) There are several types of nomenclatural types existing, such as  Holotype  Isotype  Syntype  Paratype
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  BOTANY 25/11/2021 TAXONOMY GFGCYELAHANKA P B Mallikharjuna,PhD Page 6  Lectotype  Neotype 1. HOLOTYPE: is the type specimen or other element used or designated by the author in the original publication as the main nomenclatural type. At present, it is essential that a holotype designated for a newly described species be deposited in a national herbarium like the Central National Herbarium (CAL), Calcutta of the BSI. 2. ISOTYPE: is the duplicate specimen of a holotype. There are plants forming part of the same gathering as the holotype and gathered at the same time. In the absence of holotype, isotype will serve as the nomenclatural type. 3. SYNTYPE: is one or two or more specimens studied and cited by the author, when the holotype is not designated by him. 4. PARATYPE: is a specimen cited with the original description in addition to the holotype. When the author fails to designate a holotype or the holotype is missing, a lectotype or neotype is selected to serve as a nomenclatural type. 5. LECTOTYPE: is a specimen selected from those cited by the author with the original description. 6. NEOTYPE: is selected only when all the original specimens collected and cited by the author missing. For example: Impatiens thomsonii Hook.f., is a member of the family Balsaminaceae and its description is given in the Flora of British India. The author (J D Hooker) has cited three specimens on which the description was based on. 1. Collected by Thomson from Piti and Kunawar. 2. Collected by Strach. and Wint. from the Kouman and Garhwall hills. 3. Collected by JD Hooker from Sikkim. Hooker stated that specimen 3 of the above is the nomenclatural type (i.e., Holotype). Specimens 1 and 2 are the Paratype. If Hooker had not designated the 3rd specimen as holotype, then all three were Syntypes. One of these syntypes can serve as a Lectotype, if the type holotype is missing. If all 3 specimens are destroyed for some reason, then the 4th specimen (Collected by Wallich from Sikkim,) which does not find mention in Hookers description, will be treated as a Neotype.
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  BOTANY 25/11/2021 TAXONOMY GFGCYELAHANKA P B Mallikharjuna,PhD Page 7 Additional Information: o Basionym is a technical term used in the scientific name of organisms. Basionym means the 'original name'. The term is primarily used in botanical nomenclature, and is regulated by the ICBN (Art.6.10). The term 'basionym' is used to indicate which name was the original, validly published name of the taxon. For instance, when the binomial name of a species has been changed, the earliest name is the basionym. For example, the basionym of the name Picea abies is Pinus abies. The species was originally named Pinus abies by Carolus Linnaeus; later on, botanist Karsten decided this species should not be grouped in the same genus Pinus as the pines, but in a separate genus, so he transferred it to the genus Picea. o Autonym: The automatically established name of a subdivision of a genus or of an infraspecific taxon that includes the type of the adopted, legitimate name of the genus or species, respectively. Its final epithet repeats unaltered the generic name or specific epithet and is not followed by an author citation (Art. 22.1 and 26.1). Autonyms need not be effectively published nor comply with the provisions for valid publication (Art. 32.1), they are automatically established, at any given rank, by the first instance of valid publication at that rank of a name of a subdivision of a genus under a legitimate generic name or of a name of an infraspecific taxon under a legitimate species name (Art. 22.3 and 26.3). o Isonym: The same name based on the same type, published independently at different times perhaps by different authors. Note: only the earliest isonym has nomenclatural status (Art. 6 Note 2; but see Art. 14.14). o Homonym: A name spelled exactly like another name published for a taxon at the same rank based on a different type (Art. 53.1). Note: names of subdivisions of the same genus or of infraspecific taxa within the same species that are based on different types and have the same final epithet are homonyms, even if they differ in rank (Art. 53.3), because the rank-denoting term is not part of the name (Art. 21 Note 1 and Art. 24 Note 2) (see also confusingly similar names). o Tautonym. A binary designation in which the specific epithet exactly repeats the generic name (Art. 23.4), usually not applicable to plants but common in animals, Ex. Bubo bubo (owl) o Nothospecies: A hybrid species (Art. 3.2). Source: https://www.iapt-taxon.org/nomen/pages/main/glossary.html