Patagonian opossum

Patagonian Opossum
Conservation status

Least Concern  (IUCN 3.1)[1]
Scientific classification
Kingdom: Animalia
Class: Mammalia
Infraclass: Marsupialia
Order: Didelphimorphia
Family: Didelphidae
Subfamily: Didelphinae
Genus: Lestodelphys
Tate, 1934
Species: L. halli
Binomial name
Lestodelphys halli
(Thomas, 1921)
Patagonian Opossum range

The Patagonian opossum (Lestodelphys halli) is the sole species in genus Lestodelphys.[2]

Distribution

Patagonian opossums occur further south, in Argentina, than any other living marsupial. Although it is distributed throughout some parts of southern Argentina, the Patagonian opossum is one of the least known mammals of South America.[3] Mammalogists have spot Patagonian opossums near Monte Phytogeographic Province, and in Patagonia Phytogeographic Province, yet there hasn't been any records of Patagonian opossum in Central Patagonia which leds Mammalogist to believe that they can only live in the Patagonian steppe. There are two common areas in the Patagonian steppe where these animals are often found- the province of La Pampa, and Choele Choel (north of Rio Negro Province).[4]

Form

It is suggested that the Patagonian opossum may have emerged from the same ancestral group as the Marmosa. The two species have conformed rather closely to each other. In the winter both species show similarly thick tails at the base, this is used to accumlate fat to that reigon of the tail. Yet they do not share all aspects of their life, Patagonian opossums has 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 allows the Patagonian opossum to experience an increase in biting power. [5]

General Characteristics

The general appearance of the Patagonian opossum is similar to that of the Marmosa, except they have specialized features due to their predatorial way of life. Unlike the Marmosa, their skull has a reduced muzzle, wider zygomatic arch, as well as a crowded premolar reigon. 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 reigon 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. [6]

Dentition

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 are 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. [7] The premolars increase in size from the first premolar to the third premolar. The first premolar is very reduced in size compare to the other premolar. 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.[8]

Diet

Being a member of the Didelphidae (opossum), 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 reigons has led the Patagonian opossum to feed on mainly birds and mice.[9] 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.[10]

References

  1. ↑ Costa, L., Astua de Moraes, D., Brito, D., Soriano, P., Lew, D. & Delgado, C. (2008). Lestodelphys halli. In: IUCN 2008. IUCN Red List of Threatened Species. Retrieved 28 December 2008. Database entry includes justification for why this species is of least concern
  2. ↑ Gardner, A. L. (2005). "Order Didelphimorphia". In Wilson, D. E.; Reeder, D. M. Mammal Species of the World (3rd ed.). Johns Hopkins University Press. p. 8. ISBN 978-0-8018-8221-0. OCLC 62265494.
  3. ↑ BIRNI-:Y. H. C . J. A. MONJEALI. C. J. PIUI.I-IPS. R. S. SIKES. AND I. KIM. 1996a. Lf.sUHletplixs halli: new information un a poorly known Argentine tiiarsupial. Mastozoologi'a Neotropical 3:171-181.
  4. ↑ Sauthier, Daniel Edgardo Udrizar. "Marsupialia, Didelphidae, Lestodelphys halli: New records, distribution extension and filling gaps." Mammalia. (2007): n
  5. ↑ Tate, G. H. H. 1933. A systematic revision of the marsupial genus Marmosa. Bull. Amer. Mus. Nat. Hist. 66:1-250. - 1934. New generic names for two South American marsupials. Jour. Mammal. 15:154.
  6. ↑ Thomas, O. 1921. A new genus of opossum from southern Patagonia. Ann. Mag. Nat. Hist., ser. 9, 8:136-139
  7. ↑ Gabrif, Martin. "INTRASPECIFIC VARIATION IN LESTODELPHYS HALLI (MARSUPIALIA: DIDELPHIMORPHIA)." Journal of Mammology. 86.4 (2005): 793-803
  8. ↑ Thomas, O. 1921. A new genus of opossum from southern Patagonia. Ann. Mag. Nat. Hist., ser. 9, 8:136-139
  9. ↑ Thomas, O. 1921. A new genus of opossum from southern Patagonia. Ann. Mag. Nat. Hist., ser. 9, 8:136-139
  10. ↑ Walker, E. P. et al. 1968. Mammals of the World. Johns Hopkins Press, Baltimore, 2nd ed., 2vols., 1500pp