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62-467: Ruptiliocarpon is a monotypic genus of flowering plants in the family Lepidobotryaceae . The genus has only one species , Ruptiliocarpon caracolito . It is a tall tree that grows in several small isolated areas of Central and South America . It is known from Costa Rica , Colombia , Peru , and Suriname . It is locally common on hillsides and other well-drained areas, often in red clay , from near sea level to 400 m in elevation. The seed

124-602: A common ancestor ) or paraphyletic (excluding some descendants), these concepts do not apply to monotypic taxa because they contain only a single member. Monotypic taxa are part of a broader challenge in biological classification known as aphyly – situations where evolutionary relationships are poorly supported by evidence. This includes both monotypic groups and cases where traditional groupings are found to be artificial. Understanding how monotypic taxa fit into this bigger picture helps identify areas needing further research. The German lichenologist Robert Lücking suggests that

186-482: A hierarchical system. When taxonomists identify a monotypic taxon, this often reflects uncertainty about its relationships rather than true evolutionary isolation . This uncertainty is evident in many cases across different species. For instance, the diatom Licmophora juergensii is placed in a monotypic genus because scientists have not yet found clear evidence of its relationships to other species. Some taxonomists argue against monotypic taxa because they reduce

248-447: A museum or herbarium research collection, but failing that, an image of an individual of that taxon has sometimes been designated as a type. Describing species and appointing type specimens is part of scientific nomenclature and alpha taxonomy . When identifying material, a scientist attempts to apply a taxon name to a specimen or group of specimens based on their understanding of the relevant taxa, based on (at least) having read

310-407: A clonotype. In zoological nomenclature , the type of a species or subspecies is a specimen or series of specimens. The type of a genus or subgenus is a species. The type of a suprageneric taxon (e.g., family, etc.) is a genus. Names higher than superfamily rank do not have types. A "name-bearing type" is a specimen or image that "provides the objective standard of reference whereby the application of

372-414: A diagnosis (typically, a discussion of similarities to and differences from closely related species), and an indication of where the type specimen or specimens are deposited for examination. The geographical location where a type specimen was originally found is known as its type locality . In the case of parasites, the term type host (or symbiotype) is used to indicate the host organism from which

434-418: A family. Some examples of monotypic groups are: Biological type In biology , a type is a particular specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally associated. In other words, a type is an example that serves to anchor or centralizes the defining features of that particular taxon . In older usage (pre-1900 in botany),

496-410: A lot of small plants), dead and kept safe, "curated", in a herbarium (or the equivalent for fungi). Examples of where an illustration may serve as a type include: A type does not determine the circumscription of the taxon. For example, the common dandelion is a controversial taxon: some botanists consider it to consist of over a hundred species, and others regard it as a single species. The type of

558-553: A natural classification. From a cladistic perspective, which focuses on shared derived characteristics to determine evolutionary relationships, the theoretical status of monotypic taxa is complex. Some argue they can only be justified when relationships cannot be resolved through synapomorphies (shared derived characteristics); otherwise, they would necessarily exclude related species and thus be paraphyletic. However, others contend that while most taxonomic groups can be classified as either monophyletic (containing all descendants of

620-475: A new generic name; the old generic name passes into synonymy and is abandoned unless there is a pressing need to make an exception (decided case-by-case, via petition to the International Commission on Zoological Nomenclature). A type genus is a genus from which the name of a family or subfamily is formed. As with type species, the type genus is not necessarily the most representative but is usually

682-535: A part of it that has been stolen, or improperly relocated. Type illustrations have also been used by zoologists, as in the case of the Réunion parakeet , which is known only from historical illustrations and descriptions. Recently, some species have been described where the type specimen was released alive back into the wild, such as the Bulo Burti boubou (a bushshrike ), described as Laniarius liberatus , in which

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744-403: A passing remark on Linnaeus's contributions, "Linnaeus himself, must stand as the type of his Homo sapiens. He justified his choice by noting that the specimen that Linnaeus, who wrote his own autobiography five times, had most studied was probably himself. This sufficiently and correctly designated Linnaeus to be the lectotype for Homo sapiens . It has also been suggested that Edward Cope

806-542: A precise set of rules laid down in the International Code of Zoological Nomenclature (ICZN) and the International Code of Nomenclature for algae, fungi, and plants (ICN), the scientific name of every taxon is almost always based on one particular specimen , or in some cases specimens. Types are of great significance to biologists, especially to taxonomists . Types are usually physical specimens that are kept in

868-614: A relationship with Phyllanthaceae, a family that the authors did not consider to be separate from Euphorbiaceae. Cedro caracolito is not a cedar in the strictest sense, but in Spanish , the term cedro is applied to a wide variety of trees. In Costa Rica, where most of the specimens were collected, the term cedro , with a qualifying adjective, is applied to Carapa (Meliaceae), Cedrela (Meliaceae), Tapirira ( Anacardiaceae ), and Calophyllum ( Clusiaceae ). Ruptiliocarpon caracolito has long been known to local inhabitants, but it

930-453: A single type specimen, a holotype, was often not designated. Also, types were not always carefully preserved, and intervening events such as wars and fires have resulted in the destruction of the original type material. The validity of a species name often rests upon the availability of original type specimens; or, if the type cannot be found, or one has never existed, upon the clarity of the description. The ICZN has existed only since 1961 when

992-520: A tube, which secretes nectar . Five anthers are attached to the top of the tube, and between them, five more are mounted on short filaments . The ovary has two compartments that are separated by a partition. The ovules are attached to the partition, near its top. The two stigmas are short and attached directly to the apex of the ovary. The fruit is a capsule , 2.5 to 3.5 cm long and 1.5 to 2.5 cm wide, containing one, or rarely, two seeds . The capsule breaks up and its pieces fall, leaving

1054-405: A type specimen and publishes a new name and an official description. Depending on the nomenclature code applied to the organism in question, a type can be a specimen, a culture, an illustration , or (under the bacteriological code) a description. Some codes consider a subordinate taxon to be the type, but under the botanical code, the type is always a specimen or illustration. For example, in

1116-442: A type was a taxon rather than a specimen. A taxon is a scientifically named grouping of organisms with other like organisms, a set that includes some organisms and excludes others, based on a detailed published description (for example a species description ) and on the provision of type material, which is usually available to scientists for examination in a major museum research collection, or similar institution. According to

1178-443: Is a specimen later selected to serve as the single type specimen for species originally described from a set of syntypes . In zoology, a lectotype is a kind of name-bearing type . When a species was originally described on the basis of a name-bearing type consisting of multiple specimens, one of those may be designated as the lectotype. Having a single name-bearing type reduces the potential for confusion, especially considering that it

1240-456: Is any additional specimen from among a set of syntypes after a lectotype has been designated from among them. These are not name-bearing types. A special case in Protistans where the type consists of two or more specimens of "directly related individuals" within a preparation medium such as a blood smear. The terms parahapantotype and lectohapantotype refer to type preparations additional to

1302-425: Is clearly designated in the original description, this specimen is known as the holotype of that species. The holotype is typically placed in a major museum, or similar well-known public collection, so that it is freely available for later examination by other biologists. When the original description designated a holotype, there may be additional specimens that the author designates as additional representatives of

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1364-402: Is known as "Gregg's Paradox": if a single species is the only member of multiple hierarchical levels (for example, being the only species in its genus, which is the only genus in its family), then each level needs a distinct definition to maintain logical structure. Otherwise, the different taxonomic ranks become effectively identical, which creates problems for organizing biological diversity in

1426-425: 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 variations, though this

1488-454: Is not uncommon for a series of syntypes to contain specimens of more than one species. Formally, Carl Linnaeus is the lectotype for Homo sapiens , designated in 1959. He published the first book considered to be part of taxonomical nomenclature, the 10th edition of Systema Naturae, which included the first description of Homo sapiens and determined all valid syntypes for the species. Crucially, in 1959, Professor William Stearne wrote in

1550-411: Is one of many species that are based on illustrations by Albertus Seba (1734). An ergatotype is a specimen selected to represent a worker member in hymenopterans which have polymorphic castes. A hypotype is a specimen whose details have previously been published that is used in a supplementary figure or description of the species. The term " kleptotype " informally refers to a type specimen or

1612-407: Is particularly associated with island species. Among 25 documented extinct monotypic genera studied, 22 occurred on islands, with flightless animals being particularly vulnerable to human impacts. Just as the term monotypic is used to describe a taxon including only one subdivision, the contained taxon can also be referred to as monotypic within the higher-level taxon, e.g. a genus monotypic within

1674-459: Is rarely chosen to be the case, as it makes it hard to determine to which population the individual belonged. The usage of the term type is somewhat complicated by slightly different uses in botany and zoology . In the PhyloCode , type-based definitions are replaced by phylogenetic definitions . In some older taxonomic works the word "type" has sometimes been used differently. The meaning

1736-431: Is surrounded by two endocarps which fall away and litter the ground below. To those who live where it grows, it is known as cedro caracolito , the "little snail cedar ", because the larger of the two endocarps resembles a small shell. The wood of Ruptiliocarpon is light and used in cabinet-making, but is often overlooked by wood harvesters. Ruptiliocarpon was named and described by Barry Hammel and Nelson Zamora in

1798-607: Is the Greek word for fruit . The name describes the characteristic opening of the fruit and is an obvious difference from Lepidobotrys , the other member of the family. Though some language purists frown on the creation of hybrid names, and the ICBN discourages it, Hammel and Zamora created this name because, as they said, "we consider the purely Greek or Latin options decidedly inelegant". When Hammel and Zamora described Ruptiliocarpon , two other detailed studies of its anatomy were published at

1860-485: Is the lectotype for Homo sapiens , based on the 1994 reporting by Louie Psihoyos of an unpublished proposal by Bob Bakker to do so. However, this designation is invalid both because Edward Cope was not one of the specimens described in Systema Naturae 10th Ed., and therefore not being a syntype is not eligible, and because Stearne's designation in 1959 has seniority and invalidates future designations. A paralectotype

1922-405: The stem . The leaf blade is elliptic in shape and the margin is entire . The leaves appear simple, but are actually compound and unifoliate . The leaf consists of a single leaflet on the end of a rachis . The petiolule is swollen for its entire length and a conspicuous joint separates it from the rachis. This joint bears a single, elongate stipel . There is a pair of fused stipules at

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1984-481: The base of the petiole . The stipel and stipules soon fall away. The inflorescence is an irregular arrangement of several spikes attached opposite a leaf. The flowers are small and green with five sepals and five petals that are nearly alike. The flower bud opens only slightly, producing a small hole in its end. The male and female flowers are only slightly different in appearance, with each tree bearing flowers of only one sex. The 10 stamens are united into

2046-745: The common application of the term monotypic is frequently misleading, "since each taxon by definition contains exactly one type and is hence "monotypic", regardless of the total number of units", and suggests using "monospecific" for a genus with a single species, and "monotaxonomic" for a taxon containing only one unit. Species in monotypic genera tend to be more threatened with extinction than average species. Studies have found this pattern particularly pronounced in amphibians , where about 6.56% of monotypic genera are critically endangered , compared to birds and mammals where around 4.54% and 4.02% of monotypic genera face critical endangerment respectively. Studies have found that extinction of monotypic genera

2108-477: The emergence of new leaves. The flowers are small and green and they attract little attention. Because of this, and because of the short flowering time, flowering material has rarely been collected. The fruits mature by the following January and remain on the tree into February. Trees are easily grown from seed. Because R. caracolito was not botanically described until 1993, descriptions of Lepidobotryaceae from before that time are obsolete. The type material for

2170-467: The essential characteristics of the genus to which it belongs, but this is subjective and, ultimately, technically irrelevant, as it is not a requirement of the Code. If the type species proves, upon closer examination, to belong to a pre-existing genus (a common occurrence), then all of the constituent species must be either moved into the pre-existing genus or disassociated from the original type species and given

2232-432: The first edition of the Code was published. The ICZN does not always demand a type specimen for the historical validity of a species, and many "type-less" species do exist. The current edition of the Code, Article 75.3, prohibits the designation of a neotype unless there is "an exceptional need" for "clarifying the taxonomic status" of a species (Article 75.2). There are many other permutations and variations on terms using

2294-469: The hapantotype and designated by the describing author. As with other type designations the use of the prefix "Neo-", such as Neohapantotype , is employed when a replacement for the original hapantotype is designated, or when an original description did not include a designated type specimen. An illustration on which a new species or subspecies was based. For instance, the Burmese python, Python bivittatus ,

2356-427: The information content of biological classifications. As taxonomists Backlund and Bremer explain in their critique, "'Monotypic' taxa do not provide any information about the relationships of the immediately subordinate taxon". When monotypic taxa are sister to a single larger group, they might be merged into that group; however, when they are sister to multiple other groups, they may need to remain separate to maintain

2418-464: The journal Novon in 1993. They saw that it was a close relative of Lepidobotrys and made it the second member of Lepidobotryaceae. In the same paper, they wrote a reassessment of the family. Novon published two other studies of Ruptiliocarpon in the same issue. They confirmed that Ruptiliocarpon was closely related to Lepidobotrys , but came to no firm conclusions on the relationships of this pair to other groups of rosids. One study found that

2480-447: The male parts of the flower and in the opening of the fruit. In R. caracolito , the stamens have filaments that are short and united into a tube, rather than long and fused only at the base. The anthers are basifixed instead of versatile . The capsule ruptures irregularly, instead of splitting along a seam. Monotypic Monotypic taxa present several important theoretical challenges in biological classification . One key issue

2542-408: The name Taraxacum officinale is the same whether the circumscription of the species includes all those small species ( Taraxacum officinale is a "big" species) or whether the circumscription is limited to only one small species among the other hundred ( Taraxacum officinale is a "small" species). The name Taraxacum officinale is the same and the type of the name is the same, but the extent to which

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2604-517: The name actually applies varies greatly. Setting the circumscription of a taxon is done by a taxonomist in a publication. Miscellaneous notes: The ICN provides a listing of the various kinds of types (article 9 and the Glossary), the most important of which is the holotype. These are The word "type" appears in botanical literature as a part of some older terms that have no status under the ICN : for example

2666-474: The name of a nominal taxon can be determined." Although in reality biologists may examine many specimens (when available) of a new taxon before writing an official published species description, nonetheless, under the formal rules for naming species (the International Code of Zoological Nomenclature), a single type must be designated, as part of the published description. A type description must include

2728-535: The original author never cited a specimen. A syntype is any one of two or more specimens that is listed in a species description where no holotype was designated; historically, syntypes were often explicitly designated as such, and under the present ICZN this is a requirement, but modern attempts to publish species description based on syntypes are generally frowned upon by practicing taxonomists, and most are gradually being replaced by lectotypes. Those that still exist are still considered name-bearing types. A lectotype

2790-536: The research collection of the Natural History Museum in London, there is a bird specimen numbered 1886.6.24.20. This is a specimen of a kind of bird commonly known as the spotted harrier , which currently bears the scientific name Circus assimilis . This particular specimen is the holotype for that species; the name Circus assimilis refers, by definition, to the species of that particular specimen. That species

2852-504: The same species, termed paratypes. These are not name-bearing types . An allotype is a specimen of the opposite sex to the holotype, designated from among paratypes. The word was also formerly used for a specimen that shows features not seen in the holotype of a fossil. The term is not regulated by the ICZN . A neotype is a specimen later selected to serve as the single type specimen when an original holotype has been lost or destroyed or where

2914-591: The same time. These studies confirmed that Ruptiliocarpon was correctly placed in Lepidobotryaceae, but they were inconclusive about the relationships of Lepidobotryaceae to other families. The authors suggested possible relationships to the Meliaceae and Phyllanthaceae , but it is now known that Lepidobotryaceae belongs in Celastrales . In Costa Rica, R. caracolito blooms in late March and early April, soon after

2976-406: The section ... After studying the diverse forms, I came to consider them as belonging to the one and the same specific type. In botanical nomenclature , a type ( typus , nomenclatural type ), "is that element to which the name of a taxon is permanently attached." (article 7.2) In botany, a type is either a specimen or an illustration. A specimen is a real plant (or one or more parts of a plant or

3038-436: The seed and the surrounding endocarps. The endocarps then fall, leaving the seeds hanging on the tree. The seed is shiny and black with its lower third covered by an orange aril . Ruptiliocarpon caracolito is one of only two species in the family Lepidobotryaceae, the other being the small African tree Lepidobotrys staudtii . The two are much alike in being trees with alternate, elliptic, unifoliate leaves in two rows along

3100-405: The species description included DNA sequences from blood and feather samples. Assuming there is no future question as to the status of such a species, the absence of a type specimen does not invalidate the name, but it may be necessary for the future to designate a neotype for such a taxon, should any questions arise. However, in the case of the bushshrike, ornithologists have argued that the specimen

3162-632: The species is from near Limón, on the Atlantic coast of Costa Rica. It has been reported that the flowers of the South American trees are quite different from those of the Costa Rican trees, but flowering specimens from South America have not been collected. Ruptiliocarpon caracolito is a tree, 20 to 30 m, or rarely 40 m tall. The trunk is straight and 50 to 90 cm in diameter at breast height . The leaves are arranged alternately in two rows along

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3224-414: The suffix "-type" (e.g., allotype , cotype, topotype , generitype , isotype , isoneotype, isolectotype, etc.) but these are not formally regulated by the Code, and a great many are obsolete and/or idiosyncratic. However, some of these categories can potentially apply to genuine type specimens, such as a neotype; e.g., isotypic/topotypic specimens are preferred to other specimens, when they are available at

3286-415: The time a neotype is chosen (because they are from the same time and/or place as the original type). A topotype is a specimen that was obtained from the same location that the original type specimen came from. The term fixation is used by the Code for the declaration of a name-bearing type, whether by original or subsequent designation. Each genus must have a designated type species (the term "genotype"

3348-407: The twigs. The flowers are small, green or greenish, with five sepals and five petals that are nearly alike, and 10 stamens in two series. The fruit is a capsule with one or rarely, two seeds. Ruptiliocarpon caracolito differs from L. staudtii in several characters. The stigma is short, rather than elongated, and the ovary has two rather than three compartments. The most obvious differences are in

3410-424: The type description(s), preferably also based on an examination of all the type material of all of the relevant taxa. If there is more than one named type that all appear to be the same taxon, then the oldest name takes precedence and is considered to be the correct name of the material in hand. If on the other hand, the taxon appears never to have been named at all, then the scientist or another qualified expert picks

3472-406: The type specimen was obtained. Zoological collections are maintained by universities and museums. Ensuring that types are kept in good condition and made available for examination by taxonomists are two important functions of such collections. And, while there is only one holotype designated, there can be other "type" specimens, the following of which are formally defined: When a single specimen

3534-460: The wood anatomy of Ruptiliocarpon was very much like that of Lepidobotrys and shared some traits with the wood anatomy of Trichilia , a member of the family Meliaceae . The wood of Ruptiliocarpon was different from the wood of all others to which it was compared in having vestured pits on the walls of its xylem cells. Another study found some similarities in flower structure with Meliaceae, but also found that ovule and seed morphology suggested

3596-493: Was a rare and hitherto unknown color morph of a long-known species, using only the available blood and feather samples. While there is still some debate on the need to deposit actual killed individuals as type specimens, it can be observed that given proper vouchering and storage, tissue samples can be just as valuable should dispute about the validity of a species arise. The various types listed above are necessary because many species were described one or two centuries ago, when

3658-418: Was named and described by Jardine and Selby in 1828, and the holotype was placed in the museum collection so that other scientists might refer to it as necessary. At least for type 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

3720-453: Was not named and described in the botanical literature until 1993, when sufficient material for such a description was finally collected. At that time, Barry Hammel and Nelson Zamora named it Ruptiliocarpon caracolito , basing their description mostly on specimens from Costa Rica. Ruptiliocarpon is a Latin - Greek hybrid name. Ruptilio , in Latin, means "to split irregularly", and "carpon"

3782-420: Was once used for this but has been abandoned because the word has become much better known as the term for a different concept in genetics ). The description of a genus is usually based primarily on its type species, modified and expanded by the features of other included species. The generic name is permanently associated with the name-bearing type of its type species. Ideally, a type species best exemplifies

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3844-453: Was similar in the first Laws of Botanical Nomenclature , but has a meaning closer to the term taxon in some other works: Ce seul caractère permet de distinguer ce type de toutes les autres espèces de la section. ... Après avoir étudié ces diverses formes, j'en arrivai à les considérer comme appartenant à un seul et même type spécifique. Translation: This single character permits [one to] distinguish this type from all other species of

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