A tautonym is a

scientific name In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bo ...

of a species in which both parts of the name have the same spelling, such as ''

Rattus rattus The black rat (''Rattus rattus''), also known as the roof rat, ship rat, or house rat, is a common long-tailed rodent of the stereotypical rat genus ''Rattus'', in the subfamily Murinae. It likely originated in the Indian subcontinent, but is ...

''. The first part of the name is the name of the genus and the second part is referred to as the ''specific epithet'' in the ''

International Code of Nomenclature for algae, fungi, and plants The ''International Code of Nomenclature for algae, fungi, and plants'' (ICN) is the set of rules and recommendations dealing with the formal botanical names that are given to plants, fungi and a few other groups of organisms, all those "trad ...

'' and the ''specific name'' in the ''

International Code of Zoological Nomenclature The International Code of Zoological Nomenclature (ICZN) is a widely accepted convention in zoology that rules the formal scientific naming of organisms treated as animals. It is also informally known as the ICZN Code, for its publisher, the I ...

''. Tautonymy (i.e., the usage of tautonymous names) is permissible in zoological nomenclature (see List of tautonyms for examples). In past editions of the zoological Code, the term tautonym was used, but it has now been replaced by the more inclusive "tautonymous names"; these include trinomial names such as '' Gorilla gorilla gorilla'' and '' Bison bison bison''. For animals, a tautonym implicitly (though not always) indicates that the species is the

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specim ...

of its genus. This can also be indicated by a species name with the specific epithet ''typus'' or ''typicus'', although more commonly the type species is designated another way.

Botanical nomenclature

In the current rules for

botanical nomenclature Botanical nomenclature is the formal, scientific naming of plants. It is related to, but distinct from taxonomy. Plant taxonomy is concerned with grouping and classifying plants; botanical nomenclature then provides names for the results of this ...

(which apply retroactively), tautonyms are explicitly prohibited. One example of a botanical tautonym is 'Larix larix'. The earliest name for the

European larch ''Larix decidua'', the European larch, is a species of larch native to the mountains of central Europe, in the Alps and Carpathian Mountains as well as the Pyrenees, with disjunct lowland populations in northern Poland and southern Lithuania. It ...

is ''Pinus larix'' L. (1753) but

Gustav Karl Wilhelm Hermann Karsten Gustav Karl Wilhelm Hermann Karsten (6 November 1817, in Stralsund – 10 July 1908, in Zoppot) was a German botanist and geologist. Born in Stralsund, he followed the example of Alexander von Humboldt and traveled 1844-56 the northern part of S ...

did not agree with the placement of the species in ''

Pinus A pine is any conifer tree or shrub in the genus ''Pinus'' () of the family Pinaceae. ''Pinus'' is the sole genus in the subfamily Pinoideae. The World Flora Online created by the Royal Botanic Gardens, Kew and Missouri Botanical Garden ...

'' and decided to move it to ''

Larix Larches are deciduous conifers in the genus ''Larix'', of the family Pinaceae (subfamily Laricoideae). Growing from tall, they are native to much of the cooler temperate northern hemisphere, on lowlands in the north and high on mountains fu ...

'' in 1880. His proposed name created a tautonym. Under rules first established in 1906, which are applied retroactively, ''Larix larix'' cannot exist as a formal name. In such a case either the next earliest validly published name must be found, in this case ''

Larix decidua ''Larix decidua'', the European larch, is a species of larch native to the mountains of central Europe, in the Alps and Carpathian Mountains as well as the Pyrenees, with disjunct lowland populations in northern Poland and southern Lithuania. It ...

'' Mill. (1768), or (in its absence) a new epithet must be published. However, it is allowed for both parts of the name of a species to mean the same (

pleonasm Pleonasm (; , ) is redundancy in linguistic expression, such as "black darkness" or "burning fire". It is a manifestation of tautology by traditional rhetorical criteria and might be considered a fault of style. Pleonasm may also be used for em ...

), without being identical in spelling. For instance, ''Arctostaphylos uva-ursi'' means bearberry twice, in Greek and Latin respectively; ''Picea omorika'' uses the Latin and Serbian terms for a

spruce A spruce is a tree of the genus ''Picea'' (), a genus of about 35 species of coniferous evergreen trees in the family Pinaceae, found in the northern temperate and boreal (taiga) regions of the Earth. ''Picea'' is the sole genus in the subfam ...

. Instances that repeat the genus name with a slight modification, such as ''Lycopersicon lycopersicum'' (Greek and Latinized Greek, a rejected name for the

tomato The tomato is the edible berry of the plant ''Solanum lycopersicum'', commonly known as the tomato plant. The species originated in western South America, Mexico, and Central America. The Mexican Nahuatl word gave rise to the Spanish word ...

) and '' Ziziphus zizyphus'', have been contentious, but are in accord with the Code of Nomenclature.

References

External links

{{wiktionary *''International Code of Zoological Nomenclature''
Chapter 4, Art. 18 and Chapter 6, Art. 23.3.7
Biological nomenclature Reduplication Taxonomy (biology)

Botanical nomenclature

See also

References

External links