Getting information about a herbarium
- Definitions and nomenclatures-


Herbarium is a word originated from the Latin and designates a collection of plant specimens destined to Botany studies. The collections are herbarized (technique used to conserve the botanical material) and systematically arranged making them useful for references to botanical researchers and students.

The information accumulated in a herbarium are indispensable:
- To identify and localize the vulnerable species and those threatened with extinction;
- To the biological studies of the population and communities aiming to de the manipulation of the environment;
- To recuperate degenerated areas;
- To localize the geographical distribution of threatened and/or relevant commercial value species and
- To follow the blooming and fruiting season of economical values plants.
The information also represents a register about the quality of the environment in the past and the present ages.

The importance of a herbarium is due to its own purpose of making possible the identification of botanical material by comparison, of storing and preserving historical collections (like types, for example), of subsidizing studies in botanical areas, of re-establishing the ways followed by the botanist-collectors in the past, as well as being a reference to researches of other areas (Pharmacy, genetics, forestry, sanitary and agronomy engineering ).

Another very important focus is the documentation, with representative specimens of the composition of regional, national, continental or world-wise floras (through the ages), contributing in an inestimable way to the knowledge about the bio-diversity of a certain environment. The botanical and bibliographical material contained in the herbariums is also useful to environmental education and in universities.

The information gathered in a herbarium has a great utility to the environmental preservation because it registers the occurrence of endemic, rare, threatened of extinction or already extinct species in certain regions.

 
Cattleya araguaiensis
Each exemplar of a collection - exsicata - is formed by a vegetal specimen or parts of it that were herbarized, or to put it another way, a vegetal entity, dried, pressed and mounted in a white light cardboard sheet, with a attached card where the characteristics of the collected specimen and the habitat, as well as its classification according to botanical rules are registered.

According to the International Code of Botanical Nomenclature, a nomenclatural type is the entity to which the name of a taxon is permanently linked, it could be the correct name or a synonym and it is not obligatorily the more typical specimen or more representative taxon of the species (taxon: any entity taxonomic, without specify the category, it can be a genus, species, etc.).

The botanical material collected and stored in a herbarium has some categories of classification.
The nomenclatural types (From Latin: typus, i = image, statue)
 
A exemplar of type (Typus) is a botanical material collected and stored in a herbarium, used to do the original description (diagnose) of a taxonomic entity, or in another words, this material represents this species and makes it to be known by the scientific community.
"TYPUS (TYPE)" is the general name.
 
Cattleya silvana
"HOLOTYPUS"

(holo = total) is the resultant excisata (or exsicatae) of the entity collected used to do the description.
The researcher decided which one will be used as
holotype.
Brief, a holotype is the single specimen or illustration used or designated by the author, as the type of a species.

 
If the holotype has a duplicate, it is considered as "ISOTYPUS (ISOTYPE)". Or, if the entity collected has another branch or pseudobulb (for orchids), it will be considered as a isotypus or isotype (isos = equality), with the same number of the holotype register. The isotype is very important and should be send to another herbarium (different from that where the holotype is stored) for safety's sake. This measure is taken in order to guarantee the physical integrality of the type in the event of catastrophe as occurred with the European herbarium during the 2nd World War, specially with Berlin Herbarium.

 
There also is "PARATYPUS (PARATYPE)" (para = proximity, similarity) which is another material that the researcher mentions together with the one he indicated as a holotype. If, for any circumstance, he did not succeed in observing a characteristic of a flower of the holotype or anything else, he needs another material to observe, to compare, so, in this case, he designates the paratype. In a few words, it is a specimen of a type series other than the holotype, used to compare or to clarify doubts about the species.
 
 
Stellis -holotypus
Stellis - paratypus
 

 

In order to well differentiate isotype and paratype, you should observe that holotype and isotype has the same number in the register and paratype has a different number. Paratype comes from a different "harvest" and could be collected in another area, for example.
"NEOTYPUS (NEOTYPE)" (Neo = new) is the designation of a new collected specimen when there is no original material in the taxon description because the author of the classification failed to designate a type. It should be done strictly with the information in the protolog (the original description of a species)
When there is a lost or destruction of the holotype or when the author does not point out it, "LECTOTYPUS" (Lectos = chosen, limited, small) should be indicated. A specialist looks for a well conserved material and designates it to be the lectotype. According to the original material available, it could be an isotype, asintype, a isosintype, a paratype, an illustration or a photo (the choice should be done in this order). Another material is created to be used as base to identify that species. There are more categories but those are the most common.
"SINTYPUS (SYNTYPE) " (sin = junction, with) was former used when the author mentioned many entities he used for describing the species and did not specify which was the holotype, paratype, etc... Brief, a member of a taxonomic type series when no holotype is designated. Nowadays is different, the first is the holotype and the others are paratype.

" PRINCEPS (or principes, one that is first) " is the work where the species has been described, when the species is presented to the science. The researcher collects the plant in the nature, concluded that it is a new species, described it, the description is published in a scientific magazine and it is called the " princeps work ". The description should be done in Latin or at least, the diagnose, differentiating it from the closest species. Brief, the first edition of a work.



Those texts are written based on the interviews given by the volunteers staff of the Herbarium Bradeanum as well as on the printed material written by the same staff.
From left to right: Jorge Fontella Pereira (director), Fernando da Costa Pinheiro, orchid specialist, Miriam Cristina Pereira, biologist and coordinator of projects and Leonor Ribas de Andrade, master in ecology.


 
back to the summary