Hesperomys
Encyclopedia
Hesperomys is an obsolete genus
of American rodent
s. It was initially broadly defined to include most of the cricetid
rodents of the Americas, except the Arvicolinae
, but later became restricted to the members of the modern genus Calomys; the latter name has been in use for this genus instead of Hesperomys since 1962.
in 1839 for the American rodents with cusps arranged in two series. The name combines the Greek ἑςπερος "west" and μυς "mouse". He considered it possible that species of Hesperomys would be found in the Old World, but did not doubt that the Americas were their chief abode. He included as species Mus bimaculatus (=Calomys laucha), Mus griseo-flavus (=Graomys griseoflavus), Mus Darwinii (=Phyllotis darwini), Mus zanthopygus (=Phyllotis xanthopygus), Mus galapagoensis (=Aegialomys galapagoensis), Symidon hispidum (=Sigmodon hispidus), Mus leucopus (=Peromyscus leucopus), and the woodrats (Neotoma).
In following years, authors like Johann Andreas Wagner
and Spencer Fullerton Baird
expanded the genus to include additional American species, such as those placed now in Scapteromys
, Oxymycterus
, Abrothrix
, and Peromyscus
. In 1874, Elliott Coues
designated Mus bimaculatus Waterhouse as the type species
of Hesperomys. In 1887, Herluf Winge
used Hesperomys in a sense similar to modern Calomys (but confusingly placed species related to what is now known as Oryzomys in Calomys), but in 1888 Oldfield Thomas
argued that Hesperomys could not be separated from the hamster
s (Cricetus). In 1896, however, he united it with Eligmodontia
instead, where it remained until he reinstated it for modern Calomys in 1916. He did not use Calomys (introduced by Waterhouse in 1837 for Mus bimaculatus), because he thought it to be preoccupied by an earlier name Callomys d'Orbigny and Geoffroy, 1830. In 1962, Philip Hershkovitz
noted that the International Code of Zoological Nomenclature
mandates that a name cannot be considered preoccupied even when it differs by only one letter from another, so Callomys cannot invalidate Calomys. As Calomys Waterhouse, 1837, and Hesperomys Waterhouse, 1839, both had Mus bimaculatus as their type species, the two are objective synonyms and the older name, Calomys, prevails; since then, Hesperomys has no longer been in use as a valid name.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of American rodent
Rodent
Rodentia is an order of mammals also known as rodents, characterised by two continuously growing incisors in the upper and lower jaws which must be kept short by gnawing....
s. It was initially broadly defined to include most of the cricetid
Cricetidae
The Cricetidae are a family of rodents in the large and complex superfamily Muroidea. It includes true hamsters, voles, lemmings, and New World rats and mice...
rodents of the Americas, except the Arvicolinae
Arvicolinae
The Arvicolinae are a subfamily of rodents that includes the voles, lemmings, and muskrats. They are most closely related to the other subfamilies in the Cricetidae . Some authorities place the subfamily Arvicolinae in the family Muridae along with all other members of the superfamily Muroidea...
, but later became restricted to the members of the modern genus Calomys; the latter name has been in use for this genus instead of Hesperomys since 1962.
History
Hesperomys was introduced by George Robert WaterhouseGeorge Robert Waterhouse
George Robert Waterhouse was an English naturalist.In 1833, Waterhouse was elected as the Royal Entomological Society of London's librarian and curator of insects and records....
in 1839 for the American rodents with cusps arranged in two series. The name combines the Greek ἑςπερος "west" and μυς "mouse". He considered it possible that species of Hesperomys would be found in the Old World, but did not doubt that the Americas were their chief abode. He included as species Mus bimaculatus (=Calomys laucha), Mus griseo-flavus (=Graomys griseoflavus), Mus Darwinii (=Phyllotis darwini), Mus zanthopygus (=Phyllotis xanthopygus), Mus galapagoensis (=Aegialomys galapagoensis), Symidon hispidum (=Sigmodon hispidus), Mus leucopus (=Peromyscus leucopus), and the woodrats (Neotoma).
In following years, authors like Johann Andreas Wagner
Johann Andreas Wagner
Johann Andreas Wagner was a German palaeontologist, zoologist and archaeologist.Wagner was a professor at the University of Munich, and curator of the Zoologische Staatssammlung ....
and Spencer Fullerton Baird
Spencer Fullerton Baird
Spencer Fullerton Baird was an American ornithologist, ichthyologist and herpetologist. Starting in 1850 he was assistant-secretary and later secretary of the Smithsonian Institution in Washington, D.C...
expanded the genus to include additional American species, such as those placed now in Scapteromys
Scapteromys
Scapteromys is a genus of South American rodents in the tribe Akodontini of family Cricetidae. Two species are known, found in northern Argentina, southern Brazil, Paraguay and Uruguay...
, Oxymycterus
Oxymycterus
Oxymycterus is the genus of hocicudos. They are rat-like animals endemic to South America.Species listing:Oxymycterus is the genus of hocicudos. They are rat-like animals endemic to South America.Species listing:...
, Abrothrix
Abrothrix
Abrothrix is a genus of rodent in the tribe Abrotrichini of family Cricetidae.It contains the following living species:*Abrothrix andinus*Abrothrix hershkovitzi*Abrothrix illuteus*Abrothrix jelskii*Abrothrix lanosus...
, and Peromyscus
Peromyscus
The genus Peromyscus contains the animal species commonly referred to as deer mice. This is a genus of New World mouse only distantly related to the common house mouse and laboratory mouse, Mus musculus...
. In 1874, Elliott Coues
Elliott Coues
Elliott Coues was an American army surgeon, historian, ornithologist and author.Coues was born in Portsmouth, New Hampshire. He graduated at Columbian University, Washington, D.C., in 1861, and at the Medical school of that institution in 1863...
designated Mus bimaculatus Waterhouse as the type species
Type species
In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...
of Hesperomys. In 1887, Herluf Winge
Herluf Winge
Adolf Herluf Winge was a Danish zoologist.-Biography:As a young student, Winge was interested in small mammals, particularly moles, shrews and insectivora. He studied mammalian dentition and produced a comparison of cusp similarities...
used Hesperomys in a sense similar to modern Calomys (but confusingly placed species related to what is now known as Oryzomys in Calomys), but in 1888 Oldfield Thomas
Oldfield Thomas
Oldfield Thomas FRS was a British zoologist.Thomas worked at the Natural History Museum on mammals, describing about 2,000 new species and sub-species for the first time. He was appointed to the Museum Secretary's office in 1876, transferring to the Zoological Department in 1878...
argued that Hesperomys could not be separated from the hamster
Hamster
Hamsters are rodents belonging to the subfamily Cricetinae. The subfamily contains about 25 species, classified in six or seven genera....
s (Cricetus). In 1896, however, he united it with Eligmodontia
Eligmodontia
The genus Eligmodontia consists of five or six species of South American sigmodontine mice restricted to Bolivia, Chile, and Argentina. Species of Eligmodontia occur along the eastern side of the Andes Mountains, in Patagonia, and in the Chaco thorn forest of South America. They can be found in...
instead, where it remained until he reinstated it for modern Calomys in 1916. He did not use Calomys (introduced by Waterhouse in 1837 for Mus bimaculatus), because he thought it to be preoccupied by an earlier name Callomys d'Orbigny and Geoffroy, 1830. In 1962, Philip Hershkovitz
Philip Hershkovitz
Philip Hershkovitz was an American mammalogist. Born in Pittsburgh, he attended the Universities of Pittsburgh and Michigan and lived in South America collecting mammals. In 1947, he was appointed a curator at the Field Museum of Natural History in Chicago and he continued to work there until his...
noted that the International Code of Zoological Nomenclature
International Code of Zoological Nomenclature
The International Code of Zoological Nomenclature is a widely accepted convention in zoology that rules the formal scientific naming of organisms treated as animals...
mandates that a name cannot be considered preoccupied even when it differs by only one letter from another, so Callomys cannot invalidate Calomys. As Calomys Waterhouse, 1837, and Hesperomys Waterhouse, 1839, both had Mus bimaculatus as their type species, the two are objective synonyms and the older name, Calomys, prevails; since then, Hesperomys has no longer been in use as a valid name.
Literature cited
- Hershkovitz, P. 1962. Evolution of Neotropical cricetine rodents (Muridae) with special reference to the phyllotine group. Fieldiana Zoology 46:1–524.
- Musser, G.G. and Carleton, M.D. 2005. Superfamily Muroidea. Pp. 894–1531 in Wilson, D.E. and Reeder, D.M. (eds.). Mammal Species of the World: a taxonomic and geographic reference. 3rd ed. Baltimore: The Johns Hopkins University Press, 2 vols., 2142 pp. ISBN 978-0-8018-8221-0
- Tate, G.H.H. 1932. The taxonomic history of the South and Central American cricetid rodents of the genus Oryzomys. Part 1, Subgenus Oryzomys. American Museum Novitates 579:1–18.
- Waterhouse, G.R. 1839. The Zoology of the Voyage of H.M.S. Beagle, under the command of Captain Fitzroy, R.N., during the years 1832 to 1836. Part II: Mammalia. London: Smith, Elder & Co., 80 pp.
- Weksler, M., Percequillo, A.R. and Voss, R.S. 2006. Ten new genera of oryzomyine rodents (Cricetidae: Sigmodontinae). American Museum Novitates 3537:1–29.