Answers to Nomenclature Homework

Note: In the answers, remember that underlining and italics are interchangable for scientific names; on this computer document everything is italics.

1. Correct the following or point out what is wrong (there can be more than one error per line):

  • amaranthus Albus (note: "albus" is a Latin adjective that means "white")
    Answer: Capitalize the name of the genus, put the specific epithet in lower case, underline the specific epithet. Amaranthus albus

  • Rosa carolina villosa
    This is a dreaded trinomial! There has to be some indication of the rank for "villosa".
    Some answers are (be sure to note what is italicized (or underlined) and what is not):
  • Cornus florida cloud nine
    It should be obvious that "cloud nine" is in English and hence a cultivar name. Hence, the answer is either:
    Cornus florida 'Cloud Nine' or
    Cornus florida cv. Cloud Nine

  • Rosa carolina fragrans, foliis medio tenus serratis
    A polynomial, not a binomial name, hence it is not a valid plant name. Here, Rose carolina would be correct, as would Rosa carolina subsp. fragrans var. foliis f. medio.

  • Viola x bernardii
    This is an interspecific hybrid. Do not underline or italicize the multiplication sign (x). Both names should be underlined or italicized.

  • Malus baccata var. 'Gracilis'
    There are several problems. First, the word "var." should not be underlined. The single quotation marks around "Gracilis" should be removed. The word "Gracilis" should not be capitalized. The word "gracilis" should be underlined. One answer is then: Malus baccata var. gracilis. Alternatively, one could interpret that 'Gracilis' is the name of a cultivar, in which case the correct name is: Malus baccata 'Gracilis'

  • Tilia cordata cv. greenspire
    The answer is Tilia cordata cv. Greenspire

  • Amaranthus spinosus Linnaeus
    Do not underline or italicize the name of the authority, Linnaeus, hence:
    Amaranthus spinosus Linnaeus

  • Malus baccata mandschurica
    The dreaded trinomial again. If mandschurica is considered to be a cultivar, then correct answers are: Malus baccata cv. Mandschurica or Malus baccata 'Mandschurica'. If mandschurica is considered to be part of the subspecific hierarchy, then these are correct: Malus baccata subsp. mandschurica, Malus baccata var. mandschurica or Malus baccata f. mandschurica.

  • Phlox var. amplexicaulis
    As part of the taxonomic hierarchy, all varieties must belong to a species, but there is no specific epithet given here. Also, Phlox and amplexicaulis should be underlined. Make up a species or remove the word "var." One correct answer would be: Phlox amplexicaulis.

  • Quercus alba x Q. macrocarpa = Q. x bebbiana
    The answer is : Quercus x bebbiana [Note that the "x" should be a multlication sign, which is neither underlined or capitalized.]

  • Gleditsia triacanthos 'Sunburst
    The word "Sunburst" is in English, thus it is a cultivar name. It is possible to have a cultivar at any rank below the name of genus, so a perfectly acceptable cultivar name is:
    Gleditsia triacanthos 'Sunburst' or Gleditsia triacanthos cv. Sunburst. When using quotes, make sure both are present! Italicize the specific epithet "triacanthos, but not the cultivar name.

    2. The scientific name of a species is Magnolia grandiflora Linnaeus.
    The word " Magnolia " is the genus
    The word " grandiflora " is the specific epithet
    The word "Linnaeus" is the authority

    3. True or false:
    Magnoliaceae is the name of an order -- FALSE, Magnoliaceae is the name of a family
    Liliopsida is the name of a division -- FALSE, Liliopsida is the name of a class
    The plural of "genus" is "genera" -- TRUE
    The singular of "species" is "specie" -- FALSE, never-ever use "specie" in biology!
    The pronunciation of Aloe (as the name of a genus) is al-o -- FALSE, see Class Notes, pages 32; Latin does not have silent last letters.

    4. Apple 'Macintosh' is the name of a computer as well as the common name of a cultivar of apples that we often eat. All apples belong to the genus Malus and the specific epithet of the cultivated apple is pumila. So, what is the scientific name of the Macintosh apple?
    While wonderful computers, the word "Apple" is obiously an English name and could not be the name of a genus. The correct scientific name for the Macintosh apple that you buy at the grocery store is: Malus pumila 'Macintosh'.

    5. The name of the genus for a group of plants we commonly call "redbuds" is Cercis. It belongs to the family Fabaceae. Linnaeus gave the specific epithet of canadensis to the native redbud that occurs here in Illinois. What is the complete scientific name of this species?
    The answer is:
    Cercis canadensis Linnaeus

    6. Most redbud trees belonging to the species in question 5 have green leaves. However, some trees in cultivation have leaves that are purple throughout the growing season, and these are given the cultivar name of 'Forest Pansy.' Write out the two correct ways of the scientific name of this cultivar.
    The answer is:
    Cercis canadensis cv. Forest Pansy or Cercis canadensis 'Forest Pansy'

    7. Most redbud trees have dark pink/mauve flowers. In Missouri, a few trees occur in the wild that have white flowers; this color form has been propagated and the plants are also in cultivation. Alfred Rehder described these white-flowered plants as a botanical form, using the epithet of alba. What is the complete scientific name of the white-flowered redbud?
    The answer is:
    Cercis canadensis forma alba [or Cercis canadensis Linnaeus forma alba Rehder]

    8. Species often get described more than one time. All of the following names are synonyms; that is they all refer to what we consider today to be the same species. What is the correct name for the following species of Rosa ?

    The oldest name here is the correct one, Rosa multiflora Thunberg. Can you think of an occasion when the oldest name wouldn't be the correct name for the species?

    9. The genus Rosa belongs to a family, order, and subclass that are based on the stem of the genus (Ros-). It is also a dicot and a flowering plant. Write out a hierarchial classification for this situation, using proper endings (suffixes). Then add the species Rosa carolina to the hierarchy.

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