Microcavia australis (I. Geoffroy Saint-Hilaire & d'Orbigny, 1833)

Don E. Wilson, Thomas E. Lacher, Jr & Russell A. Mittermeier, 2016, Caviidae, Handbook of the Mammals of the World – Volume 6 Lagomorphs and Rodents I, Barcelona: Lynx Edicions, pp. 406-438 : 434

7.

Southern Mountain Cavy

Microcavia australis

French: Cobaye austral / German: Stdliches Zwergmeerschweinchen / Spanish: Cuy de Patagonia

Taxonomy. Cavia australis I.Geoffroy SaintHilaire & d’Orbigny, 1833 ,

“sur les bords du Rio Negro, vers le Quarante-uniéme degre,” lower Rio Negro, Argentina .

Three subspecies are recognized.

Subspecies and Distribution.

M.a.australis1.GeoffroySaint-Hilaire&d’Orbigny,1833—W&SArgentina,fromSanJuanSEtoSBuenosAiresandStoSantaCruzprovinces,andWChile(AysénRegion).

M.a.maenasThomas,1898—NWArgentina,MtsofJujuy,Salta,Catamarca,andLaRiojaprovinces.

M. a. salinia Thomas, 1921 — NW Argentina,salt flat regions of E Catamarca and E La Rioja, SW Santiago del Estero, NW Cordoba S to N San Luis provinces.

Descriptive notes. Head-body 170-245 mm, ear 14-20 mm, hindfoot 35-50 mm; weight 141-340 g. The Southern Mountain Cavy is the most abundant and well studied of the mountain cavies. It is olive-gray agouti, with a pale gray venter, sometimes washed with yellow. It has distinct white rings around eyes. It differs from its congeners, the Northern Mountain Cavy (M. niata ) and Shipton’s Mountain Cavy (M. shiptoni ), by having orthodont, instead of proodont, incisors.

Habitat. Semiarid habitats ranging from dry grasslands to thornscrub to riparian woodlands in dry gullies and also disturbed habitats including cultivated areas, rock walls, and rock piles. The Southern Mountain Cavy is frequently associated with low shrubs like Larrea (Zygophyllaceae) , where they construct burrow systems.

Food and Feeding. Southern Mountain Cavies are herbivorous and feed on leaves, grasses, shoots, buds, and fruits; they also gnaw on bark. They often climb into shrubs to feed on leaves and leap to the ground when startled.

Breeding. There have been multiple detailed studies on reproduction and social behavior of the Southern Mountain Cavy. In one study in Argentina , breeding season was c.9 months, but at a site with a more arid and seasonal climate in Argentina , breeding season was c.7 months. Mean litter size is 2-8 young, and gestation is 53-55 days. Young are born at ¢.30 g. Age at first reproduction is ¢.85 days, and females exhibit a postpartum estrus.

Activity patterns. The Southern Mountain Cavy is diurnal and is active all day and throughout the year.

Movements, Home range and Social organization. Male Southern Mountain Cavies form linear dominance hierarchies in colonies of 4-38 individuals in the Monte Desert, Argentina . Densities in grassland habitat in Buenos Aires Province, Argentina , reached 24 ind/ha. Home ranges of males average 0-75 ha, about double that offemales, and home ranges of males and females overlap. Female groups have high levels of stability and social tolerance, generally associated with a burrow system. Mating system of the Southern Mountain Cavy is promiscuous to polygynous. Female—female interactions vary from non-aggressive to cooperative.

Status and Conservation. Classified as Least Concern on The IUCN Red List. The Southern Mountain Cavy has a large distribution, is abundant, and tolerates human disturbance.

Bibliography. Adrian & Sachser (2011), Canevari & Vaccaro (2007), Contreras & Roig (1978), Dunnum (2015), Mares et al. (1989), Redford & Eisenberg (1992), Rood (1970, 1972), Taraborelli & Moreno (2009), Tognelli et al. (1995), Woods & Kilpatrick (2005).

Figures

1. Brazilian Guinea Pig (Cavia aperea), 2. Montane Guinea Pig (Cavia tschudu), 3. Shiny Guinea Pig (Cavia fulgida), 4. Sacha Guinea Pig (Cavia patzelti), 5. Greater Guinea Pig (Cavia magna), 6. Santa Catarina’s Guinea Pig (Cavia intermedia), 7. Southern Mountain Cavy (Microcavia australis), 8. Northern Mountain Cavy (Mucrocavia miata), 9. Shipton’s Mountain Cavy (Microcavia shiptoni), 10. Spix’s Yellow-toothed Cavy (Galea spixu), 11. Eastern Yellow-toothed Cavy (Galea flavidens), 12. Highland Yellow-toothed Cavy (Galea musteloides), 13. Southern Highland Yellow-toothed Cavy (Galea comes), 14. Lowland Yellow-toothed Cavy (Galea leucoblephara), 15. Greater Capybara (Hydrochoerus hydrochaeris), 16. Lesser Capybara (Hydrochoerus isthmius), 17. Rock Cavy (Kerodon rupestris), 18. Acrobatic Cavy (Kerodon acrobata), 19. Patagonian Mara (Dolichotis patagonum), 20. Chacoan Mara (Dolichotis salinicola)

Subspecies and Distribution. M.a.australis1.GeoffroySaint-Hilaire&d’Orbigny,1833—W&SArgentina,fromSanJuanSEtoSBuenosAiresandStoSantaCruzprovinces,andWChile(AysénRegion). M.a.maenasThomas,1898—NWArgentina,MtsofJujuy,Salta,Catamarca,andLaRiojaprovinces. M. a. salinia Thomas, 1921 — NW Argentina,salt flat regions of E Catamarca and E La Rioja, SW Santiago del Estero, NW Cordoba S to N San Luis provinces.