Shrew pouch rats
Shrew pouch rats | ||||||||||||
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House shrew pouch rat ( Monodelphis domestica ) |
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Systematics | ||||||||||||
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Scientific name | ||||||||||||
Monodelphis | ||||||||||||
Burnett , 1830 |
The shrew or short-tailed opossum rats ( Monodelphis ) are a genus of marsupials from the family of opossum rats (Didelphidae). With over 20 species , they are the most species-rich genus in their family.
description
As the name suggests, these animals are similar to the shrews , but they are not related to them. They are characterized by an elongated, pointed snout and a sparsely hairy tail, which is always shorter than the body. The color of the fur varies depending on the species from reddish brown to dark gray, some animals have one or three dark stripes on their backs. These animals reach a head body length of 11 to 22 centimeters, a tail length of 5 to 9 centimeters and a weight of 25 to 150 grams.
Distribution and way of life
Like all opossums, shrew pouch rats live on the American continent , their distribution area extends from Panama to northern Argentina .
Their habitat is predominantly forests or open grasslands. Although they can climb, they primarily live on the ground. They are crepuscular or nocturnal and retire to sleep in hollow tree trunks, crevices in the rock and, less often, in tree nests. Like most opossums, they are solitary animals who avoid contact with conspecifics outside of the mating season.
Shrew pouch rats are considered skilled hunters, but they are omnivores. Their diet includes small vertebrates , insects , spiders , scorpions and carrion , but also seeds and fruits.
Reproduction
Females have 11 to 17 teats but no pouch. The gestation period is 14 to 15 days, the litter size 5 to 12, sometimes up to 16 young animals. These are weaned after almost two months and sexually mature at four to five months. Under favorable circumstances, they can give birth up to four times a year; in fact, their life expectancy is so short that they often give birth only once in their life. Most animals live little more than a year or two, with the highest known age of a shrew pouch rat in human care being four years.
The species
A distinction is made between the following types:
- Subgenus Monodelphis
- Arlindos shrew pouch rat ( M. arlindoi ) occurs in central and southern Guyana and in parts of northeastern Brazil.
- The Guiana shrew pouch rat ( M. brevicaudata ) is common in Guyana and Venezuela south of the Orinoco.
- The domestic shrew rat ( Monodelphis domestica ) is native to Brazil , Paraguay and Bolivia. It often lives near humans, where it is popular as it consumes insects, spiders, and small rodents.
- The Amazon shrew rat ( M. glirina ) occurs in a broad strip that extends from the mouth of the Amazon to southeastern Peru.
- The crowned shrew pouch rat ( M. palliolata ) occurs in the north of Venezuela.
- The Santa Rosa shrew pouch rat ( M. sanctaerosae ) is only known from the type locality in the Bolivian department of Santa Cruz .
- The touan shrew rat ( M. touan ) lives in French Guiana , in Amapá and in the area between Rio Tocantins and Rio Xingu .
- Monodelphis vossi was described as a new species in 2019. It belongs to the Monodelphis glirina species group and occurs in the Brazilian state of Roraima .
- Subgenus Microdelphys
- The three-lined shrew pouch rat ( M. americana ) from northern and central Brazil is characterized by three back stripes.
- Gardner's shrew rat ( M. gardneri ) lives in central Peru.
- Ihering's shrew rat ( M. iheringi ) lives in southern Brazil.
- The red-headed shrew pouch rat ( M. scalops ) is native to southeastern Brazil.
- Subgenus Monodelphiops
- The yellow-flanked shrew rat ( M. dimidiata ) from Brazil, Uruguay and northern Argentina only gives birth to offspring once in its life and rarely grows older than a year.
- The single- stripe shrew-pouch rat ( M. unistriata ) from southeastern Brazil is marked by a stripe on the back.
- Subgenus Mygalodelphys
- The brown shrew pouch rat ( M. adusta ) lives in northwestern South America.
- Handley's shrew pouch rat ( M. handleyi ) is only known from the Peruvian province of Requena ( Loreto region ).
- Kuns shrew rat ( M. kunsi ) occurs in a large area south of the Amazon basin.
- Osgood's short-tailed opossum ( M. osgoodi ) is native to Peru and Bolivia.
- The Peruvian shrew rat ( M. peruviana ) lives in the eastern Andes in the south and in the center of Peru.
- Monodelphis pinocchio is endemic to the Mata Atlântica in southeastern Brazil.
- Reig's shrew pouch rat ( M. reigi ) is only known from a small area in eastern Venezuela and western Guyana.
- The Ronald shrew rat ( M. ronaldi ) lives in southern Peru on the left bank of the Río Madre de Dios .
- Monodelphis saci occurs in the southern Brazilian Amazon region.
- Subgenus Pyrodelphys
- The Emilia shrew rat ( M. emiliae ) is native to the Amazon basin .
threat
These animals are not followed directly, but suffer from the reduction in their habitat. The IUCN lists twelve species as endangered or threatened.
literature
- Nowak, Ronald M .: Walker's Mammals of the World . Johns Hopkins University Press, 1999 ISBN 0-8018-5789-9
supporting documents
- ↑ Diego Astua: Family Didelphidae (possums). Pages 146-156 in Don E. Wilson , Russell A. Mittermeier : Handbook of the Mammals of the World - Volume 5. Monotremes and Marsupials. Lynx Editions, 2015, ISBN 978-84-96553-99-6
- ↑ Silvia E. Pavan, Robert S. Voss: A revised subgeneric classification of short-tailed opossums (Didelphidae, Monodelphis). (American Museum novitates, no.3868)
- ↑ Silvia E. Pavan: A revision of the Monodelphis glirina group (Didelphidae: Marmosini), with a description of a new species from Roraima, Brazil. Journal of Mammalogy, January 2019, pp. 1–15 doi : 10.1093 / jmammal / gyy165
- ↑ Silvia E. Pavan: A New Species of Monodelphis (Didelphimorphia: Didelphidae) from the Brazilian Atlantic Forest. American Museum Novitates Number 3832: 1-15. 2015. doi: 10.1206 / 3832.1
- ↑ Pavan, Silvia E .; Mendes-Oliveira, Ana C .; Voss, Robert S .: A new species of Monodelphis (Didelphimorphia, Didelphidae) from the Brazilian Amazon. American Museum novitates, no.3872, February 10, 2017