Hylaeamys megacephalus

Hylaeamys megacephalus, also known as Azara's broad-headed oryzomys[2] or the large-headed rice rat,[1] is a species of rodent in the genus Hylaeamys of family Cricetidae, of which it is the type species. It is found mainly in lowland tropical rainforest from its type locality in Paraguay north through central Brazil, French Guiana, Guyana, Suriname, and Venezuela onto Trinidad and Tobago. To its west and east, other closely related species of Hylaeamys are found: H. perenensis in western Amazonia, H. acritus in Bolivia, and H. laticeps and H. oniscus in the Atlantic Forest of eastern Brazil.

Hylaeamys megacephalus
Scientific classification edit
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Rodentia
Family: Cricetidae
Subfamily: Sigmodontinae
Genus: Hylaeamys
H. megacephalus
Binomial name
Hylaeamys megacephalus
(Fischer, 1814)

Mus megacephalus Fischer, 1814
Mus capito Olfers, 1818
Oryzomys capito Cabrera, 1961
Oryzomys megacephalus Bonvicino et al., 1996
[Hylaeamys] megacephalus Weksler et al., 1996

It was first described by Spanish naturalist Félix de Azara. Based on his description, several names were given to the animal, including Mus megacephalus Fischer, 1814 and Mus capito Olfers, 1818, both of which were largely forgotten for over a century. When capito was rediscovered in 1960, it came in use (as Oryzomys capito) for a "species" that included about all species now placed in Euryoryzomys, Hylaeamys and Transandinomys. Later, its scope was restricted, most definitively in a detailed study in 1998 by Guy Musser and coworkers, who also reinstated the older name Mus megacephalus (as Oryzomys megacephalus). In subsequent years, the western Amazonian H. perenensis was reinstated as a species and both were moved to the new genus Hylaeamys, because they are not closely related to the type species of Oryzomys.


  1. ^ a b Percequillo et al., 2016
  2. ^ Musser and Carleton, 2005

Literature citedEdit

  • Musser, G.G.; Carleton, M.D.; Brothers, E.M.; Gardner, A.L. (1998). "Systematic studies of oryzomyine rodents (Muridae: Sigmodontinae): diagnoses and distributions of species formerly assigned to Oryzomys "capito"". Bulletin of the American Museum of Natural History. 236: 1–376. hdl:2246/1630.
  • Musser, G.G.; Carleton, M.D. (2005). "Superfamily Muroidea". In Wilson, D.E.; Reeder, D.M (eds.). Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Johns Hopkins University Press. p. 1151. ISBN 978-0-8018-8221-0. OCLC 62265494.
  • Percequillo, A.; Patton, J.; Pires-Costa, L.; D'Elia, G.; Patterson, B. (2016). "Hylaeamys megacephalus (errata version published in 2017)". IUCN Red List of Threatened Species. IUCN. 2016: e.T29403A115168269. Retrieved 24 December 2019.
  • Weksler, M.; Percequillo, A. R.; Voss, R. S. (2006-10-19). "Ten new genera of oryzomyine rodents (Cricetidae: Sigmodontinae)" (PDF). American Museum Novitates. New York: American Museum of Natural History. 3537: 1–29. doi:10.1206/0003-0082(2006)3537[1:TNGOOR]2.0.CO;2. hdl:2246/5815. ISSN 0003-0082.