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How to Write a Scientific Name Correctly
There are precise conventions to follow when writing a scientific name.
1. The genus name is written first.
2. The genus name is always
3. The first letter of the genus name is always capitalized
1. The specific epithet is written second.
2. The specific epithet is always
3. The first letter of the specific epithet name is never capitalized.
Scientific Name - The scientific name of this plant would appear as follows:
or Astrophytum myriostigma
Mutations? Frequently a particular individual of a species will mutate to a diverse colour, size, or
growth habit. These characteristics are passed on to its descendants (offspring’s). When this happens,
a population of plants exists with the same scientific name, but a sub-group displays different characteristics.
If the mutated group is significantly different from the parents and is stable (the traits are passed on from
generation to generation), then this new group of plants is often assigned a variety name.
A. Variety names are given when the mutation occurs in nature. (E.g. a mutation occurs in a wild arid land)
B. The abbreviation var. is used to signify that the mutation is a variety. var. is placed after the specific epithet and is not underlined or italicised.
Example: Astrophytum myriostigma var.
1. The variety name is written after var.
2. Underline or italicise the variety name.
Astrophytum myriostigma var. strongylogonum
Form (forma) Names
A. Form names are given for sporadic or minor variations occurring among individuals of any population, mainly in
horticultural applications (e.g. a mutation in spine length or flower colour)
B. The abbreviation f. is used to signify that the mutation is a form. forma (f.) is placed after the
specific epithet and is not underlined or italicised.
Example: Astrophytum myriostigma f.
1. The form name is written after forma (f.)
2. Do not capitalize the first letter (e.g. Astrophytum myriostigma f. quadricostata)
3. Underline or italicise the variety name.
Astrophytum myriostigma f. quadricostata
Mutations can also take place because of human involvement such as breeding, applying mutagens, propagation, or by
cultural practices. In these cases, the new group of mutated plants is called a cultivar. "Cultivar" is an abbreviated
form of cultivated variety. The mutated plants are assigned a cultivar name.
A. Cultivar names are given when the mutation occurs due to human influence.
Examples: a mutation occurs in a green house.
B. A cultivar is distinguished from a naturally-occurring variety by capitalizing the cultivar name and placing it in single quotes in plain type.
Example: Astrophytum myriostigma 'Onzuka'
The cultivar name is written within the single quotes.
Capitalize the cultivar name.
Never underline or italicise the cultivar name.
(An older (and now obsolete) way to indicate a cultivar is with the abbreviation cv. instead of the single quotes
- for example, : Astrophytum myriostigma cv. Onzuka.)
Author: John Chippindale, Leeds, England