Animal Diversity Web

Ge­o­graphic Range

Thy­lamys venus­tus is dis­trib­uted at low- to mid-el­e­va­tions in the Andes from Cen­tral Bo­livia south­ward into north­ern Ar­gentina. (Gi­a­rla, et al., 2010)

• Biogeographic Regions
• neotropical
  • native

Habi­tat

Thy­lamys venus­tus pri­mar­ily in­hab­its mid-level mon­tane forests and sea­son­ally dry forests be­tween 350 and 4000 me­ters above sea level in the east­ern Andes. This species over­laps in dis­tri­b­u­tion with Thy­lamys spon­so­rius, Thy­lamys pal­lid­ior, and Thy­lamys pusil­lus. (Gi­a­rla, et al., 2010)

• Habitat Regions
• tropical
• terrestrial

• Terrestrial Biomes
• forest
• mountains

• Range elevation

  350 to 4000 m

  1148.29 to 13123.36 ft

Phys­i­cal De­scrip­tion

Like other mem­bers of its genus, Thy­lamys venus­tus is no­table for its in­cras­sate (fat­tened) tail. The size of the tail varies by sea­son in ac­cor­dance with food avail­abil­ity. Al­though this species is a mar­su­pial, fe­males do not have a pouch. This species is tri­col­ored, with darker dor­sal fur, paler lat­eral fur, and a gray­ish ven­tral re­gion. This species is very sim­i­lar in mor­phol­ogy to its sis­ter species Thy­lamys spon­so­rius, though it tends to be slightly smaller. Like Thy­lamys spon­so­rius, this species has a rel­a­tively long tail that is con­sid­er­ably longer than its body. Gi­a­rla et al. (2010) re­port head and body lengths that range from 84 to 110 mm (av­er­age 96 mm) and tail lengths that range from 111 to 138 mm long (av­er­age 126 mm). (Gi­a­rla, et al., 2010)

• Other Physical Features
• endothermic
• bilateral symmetry

• Range length

  195 to 248 mm

  7.68 to 9.76 in

• Average length

  222 mm

  8.74 in

Re­pro­duc­tion

Lit­tle is known about the mat­ing sys­tem in Thy­lamys venus­tus.

Lit­tle is known about the gen­eral re­pro­duc­tive be­hav­ior of Thy­lamys venus­tus.

• Key Reproductive Features
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual
• fertilization
• viviparous

Lit­tle is known about parental in­vest­ment in Thy­lamys venus­tus. Like all mar­su­pi­als, fe­males nurse their highly al­tri­cial young. How­ever, be­cause mem­bers of the genus Thy­lamys lack a pouch (mar­supium), the young must cling to their mother's ven­ter. (Gi­a­rla, et al., 2010)

• Parental Investment
• altricial
• female parental care
• pre-fertilization
  • provisioning
  • protecting
    • female
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • female
• pre-weaning/fledging
  • provisioning
    • female
  • protecting
    • female

Lifes­pan/Longevity

No records of lifes­pan in this species are avail­able.

Be­hav­ior

Lit­tle is known about the be­hav­ior of Thy­lamys venus­tus. This species is likely soli­tary, as most small, in­sec­tiv­o­rous mam­mals are. As is the case for other mem­bers of this genus, Thy­lamys venus­tus is noc­tur­nal and ex­pe­ri­ences daily tor­por. Like other mem­bers of the genus Thy­lamys, in­di­vid­u­als likely build nests out of grass, hair, feath­ers, and leaves in rocks, trees, and under shrubs (Braun et al., 2010). Thy­lamys species are pri­mar­ily ter­res­trial but are also skilled at climb­ing bushes and small trees. (Braun, et al., 2010; Gi­a­rla, et al., 2010)

• Key Behaviors
• arboreal
• scansorial
• terricolous
• nocturnal
• motile
• sedentary
• daily torpor
• solitary

Home Range

No data on the home range of this species are avail­able.

Com­mu­ni­ca­tion and Per­cep­tion

Be­cause this species is small and noc­tur­nal, com­mu­ni­ca­tion be­tween in­di­vid­u­als is likely pri­mar­ily ol­fac­tory in na­ture. Palma (1997) re­ports that the ol­fac­tory and vi­sual re­gions of an­other Thy­lamys species' brain are es­pe­cially well de­vel­oped. (Palma, 1997)

• Communication Channels
• visual
• tactile
• acoustic
• chemical

• Perception Channels
• visual
• tactile
• acoustic
• vibrations
• chemical

Food Habits

Lit­tle is known about the food habits of this species. Like other Thy­lamys species, Thy­lamys venus­tus likely con­sumes in­sects and per­haps oc­ca­sion­ally eats small ver­te­brates, leaves, fruit, seeds, and car­rion (Palma 1997). (Palma, 1997)

• Primary Diet
• carnivore
  • insectivore

Pre­da­tion

Like other small mam­mals, Thy­lamys venus­tus is likely well adapted to avoid­ing preda­tors by being noc­tur­nal and in­con­spic­u­ous. No records of known preda­tors are avail­able.

• Anti-predator Adaptations
• cryptic

Ecosys­tem Roles

Thy­lamys venus­tus likely acts as an im­por­tant preda­tor to many arthro­pod species and per­haps some small ver­te­brates. It is likely prey to both bird and medium-sized mam­mals, such as owls and foxes. It is also likely host to many ecto- and en­dopar­a­sites. More spe­cific in­for­ma­tion about the ecosys­tem role of Thy­lamys venus­tus is not presently avail­able.

Eco­nomic Im­por­tance for Hu­mans: Pos­i­tive

There are no known pos­i­tive ef­fects of Thy­lamys venus­tus on hu­mans.

Eco­nomic Im­por­tance for Hu­mans: Neg­a­tive

There are no known neg­a­tive ef­fects of Thy­lamys venus­tus on hu­mans.

Con­ser­va­tion Sta­tus

This species is listed as "Data De­fi­cient" by the IUCN.

• IUCN Red List

  Data Deficient

Con­trib­u­tors

Tom Gi­a­rla (au­thor), Uni­ver­sity of Min­nesota, Sharon Jansa (ed­i­tor), Amer­i­can Mu­seum of Nat­ural His­tory, Robert Voss (ed­i­tor), Amer­i­can Mu­seum of Nat­ural His­tory, Tanya Dewey (ed­i­tor), Uni­ver­sity of Michi­gan-Ann Arbor.

Ref­er­ences

Braun, J., N. Pratt, M. Mares. 2010. Thy­lamys pal­lid­ior (Didel­phi­mor­phia: Didel­phi­dae). Mam­malian Species, 42(856): 90-98.

Gi­a­rla, T., R. Voss, S. Jansa. 2010. Species Lim­its and Phy­lo­ge­netic Re­la­tion­ships in the Didel­phid Mar­su­pial Genus Thy­lamys Based on Mi­to­chon­dr­ial DNA Se­quences and Mor­phol­ogy. Bul­letin of the Amer­i­can Mu­seum of Nat­ural His­tory, 346: 1-67.

Palma, R. 1997. Thy­lamys el­e­gans. Mam­malian Species, 572: 1-4.