Zygogeomys trichopus Merriam 1895
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
Zygogeomys
Zygogeomys trichopus

description: 25.
Michoacan Pocket Gopher
Zygogeomys trichopus
French: Gaufre du Michoacan / German: Michoacéan-Taschenratte / Spanish: Tuza de Michoacan
Taxonomy. Zygogeomys trichopus Merriam, 1895,
“Nahuatzin, Michoacan, Mexico.”
Two subspecies are recognized.
Subspecies and Distribution.
Z. t. trichopus Merriam, 1895 — Cerro Patamban and Cerro Tancitaro in NW Michoacan, Mexico.
7. t. tarascensis Goldman, 1938 — vicinity of Patzcuaro in C Michoacan, Mexico.
Descriptive notes. Head-body 170-240 mm, tail 60-100 mm; weight 190-580 g. Male Michoacan Pocket Gophers are usually larger than females. Dorsal pelage is short and fine, somewhat shiny, and smoky gray to lustrous brown. Ventral pelage is lighter in color and often has irregular white spots (2-4 cm diameter), especially in throat region. Tail is completely naked, and white skin oftail is almost translucent. The Michoacan Pocket Gopher has a fusiform body shape typical of all pocket gophers, and it possesses fur-lined cheek pouches that open external to the mouth. Anterior surface of each upper incisor has two distinct grooves, the larger of which is located along the midline of the tooth (offset slightly toward the inner edge of the tooth) and the smaller of which lies immediately along the inner edge of the tooth. Chromosomal complement has 2n = 40 and FN = 74.
Habitat. Deep, volcanic soils in small clearings in pine-oak-spruce forests. Elevational range is 2200 m to more than 3000 m.
Food and Feeding. There is no specific information available for this species, but the Michoacan Pocket Gopher probably feeds on roots, tubers, stems, and leaves of most plants available within the vicinity of its burrow system. 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. Main nest chamber in an excavated burrow system of a Michoacan Pocket Gopher was more than 2 m below the surface. Earthen mounds produced by the Michoacan Pocket Gopher are unlike those of any other pocket gopher in that they are tall and conical in shape (rather than low and rounded) and lack any evidence of an opening at the apex of the mound. Shape of the mound and absence of an opening (or evidence of a plugged opening) suggest that Michoacan Pocket Gophers rarely leave their burrow systems.
Breeding. Very little is known about the breeding activities of the Michoacan Pocket Gopher, except that a female with a single embryo was captured in mid-December and testes in males were small (below 5 mm) in March and August and much larger (above 14 mm) in December.
Activity patterns. The Michoacan Pocket Gopher can be active at any hour of the day but is usually more active during the night. It does not hibernate and is active year-round.
Movements, Home range and Social organization. The Michoacan Pocket Gopheris solitary and territorial. Field biologists report that it appearsto be less aggressive than most species of pocket gophers. Because it rarely leaves its burrow system except, perhaps, to disperse, its home range is defined by the size and extent ofits burrow system. One study reported that genetic variation in the Michoacan Pocket Gopher is unusually low by mammalian standards, probably as a consequence of inbreeding in small populations.
Status and Conservation. Classified as Endangered on The IUCN Red List because its range is less than 5000 km?, it is known from only three isolated localities, and there is continuing decline in the quality and extent of its habitat. The Michoacan Pocket Gopher waslisted as in danger of extinction under the Mexican Endangered Species Actin 2010.
Bibliography. Alvarez-Castafieda, Castro-Arellano, Lacher, Vazquez & Arroyo-Cabrales (2008c), Ceballos (2014), Hafner & Hafner (1982), Hafner (1984), Patton (2005b), SEMARNAT (2010).
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