Didelphis pernigra, J. A. Allen, 1900

Astúa, D., 2015, Didelphidae, Handbook of the Mammals of the World – Volume 5 Monotremes and Marsupials, Barcelona: Lynx Edicions, pp. 129-186 : 162

55.

Andean White-eared Opossum

Didelphis pernigra

French: Opossum des Andes / German: Anden-Opossum / Spanish: Zarigueya de orejas blancas andina

Other common names: Andean Opossum

Taxonomy. Didelphis pernigra J. A. Allen, 1900 ,

Peru, Puno, “ Juliaca,” Puno, Peru. Corrected by J. A. Allen in 1902 to “Inca Mines” (= Santo Domingo) .

This species is monotypic.

Distribution. NW Venezuela, Colombia, Ecuador, Peru, and W Bolivia, on forested slopes of the Andes.

Descriptive notes. Head-body 34-44 cm, tail 32-41.2 cm; weight 0-72.2 kg. Skull shape of the Andean White-eared Opossum is sexually dimorphic. Its dorsal fur, except for head,is intense shiny black, with two distinct layers: soft woolly underfur consisting of pale yellowish-white hairs (on their basal one-half) with black tips, under abundant long, not very stiff, entirely black guard hairs. White part of underfur is concealed underneath dense black outer coat. Head is white, with a clearly marked black eye mask from nose through a little behind eyes, and then continuing to bases of ears as an ill-defined dusky line. Cheeks are rusty buff or white, and there is a black line on center of forehead, narrowing to a point between eyes. Tail length is about the same as head-body length or slightly shorter, and tail is basally furred, black on proximal two-fifths to three-fifths, and white on rest. Ventral fur is buffy white, with black-tipped hairs; throat is rusty buff. Feet are black, and ears are large, entirely pinkish-white in living individuals (yellowish-white in dried skins), contrasting sharply with black dorsal fur. Females have a pouch, but number of mammae is unknown. The Andean White-eared Opossum has a 2n = 22, FN = 20 karyotype, with all acrocentric autosomes, and small acrocentric X-chromosome and Y-chromosome.

Habitat. Lower montane wet and dry forested habitats from at least elevations of 1500 m in the Andes. The Andean White-eared Opossum is also found in subparamos and paramos in Venezuela and at lower elevations in riparian habitats in the arid Pacific lowlands of Peru. It is a generalist and occurs in secondary forests, open lands, cultivated areas, and suburban areas.

Food and Feeding. There is no information available for this species.

Breeding. In Mérida, Venezuela, reproductively active female Andean White-eared Opossums were observed in February-March and then in June-July, with litters of five young (when present). In Colombia, gestation was estimated at c.12 days, and mean litter size was of 4-2 young, ranging from two to seven young.

Activity patterns. There is no information available for this species.

Movements, Home range and Social organization. In western Venezuela, the Andean White-eared Opossum has been captured much more frequently (86%) on the ground than in trees (14%).

Status and Conservation. Classified as Least Concern on The IUCN Red List. The Andean White-eared Opossum has a widespread distribution, presumably a large overall population, and occurs in several protected areas.

Bibliography. Allen (1900, 1902), Astua (2010), Barrera-Nino & Sanchez (2014), Cerqueira (1985), Cerqueira & Tribe (2007), Durant (2002), Gardner (2005), Handley (1976), Lemos & Cerqueira (2002), Mondolfi & Pérez-Hernandez (1984), Palma & Yates (1996), Tyndale-Biscoe & Mackenzie (1976), Ventura et al. (2002).

Figures

65. Pygmy Opossum (Chacodelphys formosa), 66. Agricola’s Opossum (Cryptonanus agricola), 67. Chacoan Mouse Opossum (Cryptonanus chacoensis), 68. Guaiba Mouse Opossum (Cryptonanus guahybae), 69. Unduavi Mouse Opossum (Cryptonanus unduaviensis), 70. . Emilie’s. 9 Opossum.. Gracilinanus. (null), 71. Aceramarca Opossum (Gracilinanus aceramarcae), 72. Agile Opossum (Gracilinanus agilis), 73. Wood Sprite Opossum (Gracilinanus dryas), 74. Northern Gracile Opossum (Gracilinanus marica), 75. Brazilian Gracile Opossum (Gracilinanus microtarsus)

Distribution. NW Venezuela, Colombia, Ecuador, Peru, and W Bolivia, on forested slopes of the Andes.