Patagonian opossums were previously known by the name Notodelphys halli. They are also known as Opossum De Patagonie.
There is little available information on communication and perception in Lestodelphys halli. Like all mammals, olfaction and hearing are likely to be important modes of perception. Visual and tactile cues are also important and all modes of perception may be used in interspecific communication.
Perception Channels: visual ; tactile ; acoustic ; chemical
Patagonian opossums are experiencing habitat loss and degradation in their preferred habitats, which are extensively modified for agriculture and grazing. They were classified as vulnerable in 1996 by the IUCN.
US Federal List: no special status
CITES: no special status
State of Michigan List: no special status
IUCN Red List of Threatened Species: least concern
There is little information on negative economic impacts of Lestodelphys halli.
Patagonian opossums often live in close proximity to human dwellings. Since their diet consists largely of small rodents, they are likely to help control rodent populations. Rodents often destroy farmers crops and are carriers of many diseases. The control of rodents can have a positive economic impact because their will be less disease outbreaks and less crop damage.
Positive Impacts: controls pest population
Patagonian opossums are a significant part of the diet of barn owls (Tyto alba) and Magellanic horned owls (Bubo magellanicus). Pellet remains have been collected from roosting and nesting sights. Patagonian opossums are also predators of small rodents and birds in the ecosystems in which they live.
Unlike most didelphids, which are omnivorous, Patagonian opossums are primarily carnivorous. Their diet consists mainly of small birds and rodents. A 70 gram animal has been observed eating a 35 gram mouse. Patagonian opossums have also been captured in traps baited with dead birdd. Patagonian opossums have a shortened skull, long claws, and long canine teeth, morphologies suggestive of specialization towards carnivory. These opossums will also eat fruit and insects where they are available. During winter months they may hunt under the snow or go into torpor. They also store fat at the base of their tail.
Animal Foods: birds; mammals; insects
Plant Foods: fruit
Primary Diet: carnivore (Eats terrestrial vertebrates)
Lestodelphys halli occurs farther south than any other known living marsupial species (Marshall 1977). Patagonian opossums are endemic to Argentina, particularly in the Patagonian pampas, Chubet, Mendoza, Neuquen, Rio Negro, and Santa Cruz.
Biogeographic Regions: neotropical (Native )
Patagonian opossums are terrestrial opossums. They occur mainly in areas of shrubs, grasslands, meadows, and savannahs.
Habitat Regions: tropical ; terrestrial
Terrestrial Biomes: savanna or grassland ; chaparral
There is little available information on the longevity of Lestodelphys halli.
Head and body length range from 132 to 144 millimeters and tail length from 81 to 99 millimeters. The hind foot measures between 15.7 and 17.7 millimeters and the length of the ear is between 18 and 22 millimeters. Patagonian opossums weigh between 70 and 80 grams.
The fur is short, soft and dense. The back is dark gray, the face is slightly darker with no markings, and the side of the body is gray. The forearms, hands, ankles, feet, and under parts are white. There is also a white patch over the eye and at the base of the ear. The ears are short, rounded, and flesh-colored. The tail is covered in short, fine hairs and is grayish brown above and whitish below. Males have an orange patch on the front of their throat and females have an orange patch around their nipples.
The dental formula is: I 5/4, C 1/1, P 3/3, and M 4/4, totaling 50 teeth. Lestodelphys halli has a shortened muzzle, crowded premolar region, and wide zygomatic arches. The auditory bullae are large. The canines are exceptionally long and nearly vertical.
Range mass: 70 to 80 g.
Range length: 213 to 243 mm.
Other Physical Features: endothermic ; heterothermic ; homoiothermic; bilateral symmetry
Sexual Dimorphism: sexes colored or patterned differently
Pellet samples have been collected during scientific studies from barn owls (Tyto alba) and Magellanic horned owls (Bubo magellanicus) which contained reminants of L. halli. Humans have also drastically imperiled this species through habitat degradation. It is also possible they serve as a food source to humans.
Anti-predator Adaptations: cryptic
There is little available information on mating system in Lestodelphys halli. It is likely that males and females only loosely associate for mating and that mating is promiscuous or polygynous, as in other didelphids.
Female Patagonian opossums have 19 mammae. Like all marsupials, they have a relatively short gestation period followed by a lengthy period of lactation. Little information is available on the natural history of reproduction in these opossums. Because they live in temperate regions, it is likely that they breed seasonally.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; viviparous
There is little available information on parental investment in Lestodelphys halli. As in all mammals, females gestate and nurse their young.
Parental Investment: altricial ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female)
The Patagonian opossum occurs further south, in Argentina, than any other living marsupial. Although distributed throughout some parts of southern Argentina, it is one of the least known mammals of South America. They have been spotted near Monte Phytogeographic Province, and in Patagonia Phytogeographic Province, yet there are no records of Patagonian opossums in central Patagonia, which leads mammalogists to believe that they can only live in the Patagonian steppe. There are two areas in the Patagonian steppe where these animals are often found: the province of La Pampa and Choele Choel (northern Rio Negro Province).
It is suggested that the Patagonian opossum may have emerged from the same ancestral group as Marmosa. They resemble each other closely. In the winter both types have similarly thickening at the base of the tails, where fat accumulates. Yet they do not share all aspects of their lifestyle; Patagonian opossums have a specialized way to gather and consume food, which is made possible by the shortening of their skull and jaws. The shortening occurs in the premolar region; this gives the Patagonian opossum increased biting power.
The general appearance of the Patagonian opossum is similar to that of mouse opossums, except they have specialized features due to their predatorial way of life. Unlike mouse opossums, their skull has a reduced muzzle, wider zygomatic arch, as well as a crowded premolar region. Patagonian opossums have rather short fur, that are fine and soft. Their fur are usually gray, with the posterior being dark gray, the sides being a paler shade of gray, their shoulders are dark and their cheeks as well are eye region are white in color. Their ears are short, they are a pink flesh color, with the base of their ears being white. Their tails are much shorter than their head and their body.
The Patagonian opossum has generally 50 teeth. 18 incisors, 4 canines (tooth), 12 premolars, and 16 molars (tooth). Their canine is exceptionally long, and they are almost completely straight and vertical. The first pair of incisors is set aside from the other incisors, yet all of the incisors remain the same size. Incisor number 1,3,4 on the bottom jaw are curved at the base, while incisor number 2 is straight. The premolars increase in size from the first premolar to the third premolar. The first premolar is very reduced in size compared to the other premolars. The premolars also have a distinct set of cusp on them called the posterobasal cusp. Their molars are extremely long, combine all the length of the premolar and it will barely exceed the length of the first two molars. The upper molars are narrow in size, compared to any of the other living opossums.
Being a member of the Didelphidae (opossums), Patagonian opossums feed mainly on insects and fruits, yet insects and fruits are fairly rare in far-southern habitats. The shortage of fruits and insects in southern regions has led the Patagonian opossum to feed on mainly birds and mice. One specimen of Patagonian opossum was caught using a dead bird as bait; this led some researchers to believe that the Patagonian opossum lives totally on birds.