Orthogeomys grandis
Creators: name: Don E. Wilson
name: Thomas E. Lacher, Jr
name: Russell A. Mittermeier
Publisher: name: Lynx Edicions
Year: 2016
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Mammalia
Rodentia
Geomyidae
Orthogeomys
Orthogeomys grandis

description: 26.
Giant Pocket Gopher
Orthogeomys grandis
French: Grand Gaufre / German: Riesentaschenratte / Spanish: Tuza gigante
Other common names: Oaxacan Pocket Gopher (cuniculus)
Taxonomy. Geomys grandis Thomas, 1893,
“Duenas, [Sacatépequez Province], Guatemala.”
Orthogeomys cuniculus was formerly recognized as a separate species, but it was considered indistinguishable from O. grandis scalops by T. A. Spradling and colleagues in 2016. Sixteen subspecies recognized.
Subspecies and Distribution.
O.g.grandisThomas,1893—mountainsofSGuatemala.
O.g.alleniNelson&Goldman,1930—SColimaandSEJaliscoSalongthecoasttoCOaxaca,Mexico.
O.g.alvareziSchaldach,1966—SCOaxaca,Mexico.
O.g.annexusNelson&Goldman,1933—NWChiapas,Mexico.
O.g.carboGoodwin,1956—coastalSCOaxaca,Mexico.
O.g.engelhardiFelten,1957—coastalElSalvador.
O.g.felipensisNelson&Goldman,1930—WCOaxacaintoSWPuebla,Mexico.
O.g.guerrerensisNelson&Goldman,1930—NGuerrero,Mexico.
O.g.huixtlaeVilla,1944—SChiapas,Mexico.
O.g.latifronsMerriam,1895—CoastalSGuatemala.
O.g.nelsoniMerriam,1895—NCOaxaca,Mexico.
O.g.plutoLawrence,1933—SWHonduras.
O.g.pygacanthusDickey,1928—SEGuatemalaintoElSalvador.
O.g.scalopsThomas,1894—coastalEOaxaca,Mexico.
O.g.soconuscensisVilla,1949—SWChiapas,Mexico.
O. g. vulcani Nelson & Goldman, 1931 — SW Guatemala.
Descriptive notes. Head-body 220-300 mm,tail 95-140 mm; weight 480-985 g. Male Giant Pocket Gophers are usually larger than females. Some individuals are among the largest of geomyids (more than 800 g body mass); others, particularly individuals living in dry lowland habitats, are small (less than 600 g). Specimens from elevations above 1000 m have dense, woolly fur that is dark brown to almost black. At low elevations, fur is extremely sparse over the entire body, often giving a naked appearance. In all specimens,tail is naked, and feet are nearly so. Nasal pad is sparsely haired or naked. The Giant Pocket Gopher has a fusiform body shape typical of all pocket gophers and possesses fur-lined cheek pouches that open external to the mouth. Anterior surface of each upper incisor has a single medial groove. Chromosomal complement has 2n = 58 and FN = 110.
Habitat. Deep, well-drained soils in a wide variety of habitats ranging from high-elevation cloud forests to perennial tropicalforests, tropical deciduous and semideciduous forests, and thorny xeric scrublands at low elevations. Elevational range extends from near sea level to ¢.2700 m.
Food and Feeding. There is no specific information available for this species, but the Giant Pocket Gopher probably feeds on roots, tubers, stems, and leaves of most plants available within the vicinity of its burrow system. It readily invades cultivated fields and is considered an agricultural pest wherever it occurs in contact with humans. As in all other pocket gophers, the burrow system is a series of shallow feeding tunnels radiating spoke-like from a deeper, central network that contains one or more nest chambers and several smaller chambers for storage of food or fecal pellets.
Breeding. Breeding season of the Giant Pocket Gopher likely varies widely among populations living at different elevations. At low elevations, reproductively active individuals have been captured in January-March, and typicallitter size is two young.
Activity patterns. There is no specific information available for this species, but the Giant Pocket Gopher is probably active at any hour of the day, with periods of peak activity around dawn and dusk. It does not hibernate and is active year-round.
Movements, Home range and Social organization. The Giant Pocket Gopheris solitary and aggressively territorial. Because it rarely leavesits burrow system, its home range is defined by size and extent of its burrow system. Individuals have non-overlapping home ranges, each spanning c.240 m* of surface area.
Status and Conservation. Classified as Least Concern on The IUCN Red List. The “Oaxacan Pocket Gopher” (O. cuniculus), treated here under O. g. scallops, is classified as Data Deficient.
Bibliography. Ceballos (2014), Hafner (1983), Patton (2005b), Reid (1997), Spradling et al. (2016), Vazquez, Emmons & McCarthy (2008).
description: Published as part of Don E. Wilson, Thomas E. Lacher, Jr & Russell A. Mittermeier, 2016, Geomyidae, pp. 234-269 in Handbook of the Mammals of the World – Volume 6 Lagomorphs and Rodents I, Barcelona :Lynx Edicions on page 247, DOI: 10.5281/zenodo.6603807