Animal Diversity Web

Ge­o­graphic Range

Neusti­comys mon­ti­co­lus is found in the Andes moun­tains of west Co­lum­bia and north­ern Ecuador, in par­tic­u­lar in the Cordillera Cen­tral and Oc­ci­den­tal moun­tain ranges of Co­lum­bia. (Gómez-Laverde and Del­gado, 2010; Packer and Lee, Jr., 2007; Voss, 1988)

• Biogeographic Regions
• neotropical
  • native

Habi­tat

Neusti­comys mon­ti­co­lus is often found in heav­ily wooded areas along streams and small rivulets. These streams often run through con­stricted ravines that are trib­u­taries to big­ger wa­ter­courses and even­tual rivers. Neusti­comys mon­ti­co­lus is often found near small wa­ter­falls around 2m in height and prefers river­ine habi­tat cov­ered by roots, cob­bles, moss-cov­ered rocks, gravel, and coarse sand. It has also been found in marsh-like areas sur­rounded by shrubs and shrub-like plants. This species com­monly oc­cu­pies el­e­va­tions rang­ing from 1,800 to 2,777 m. High el­e­va­tion pop­u­la­tions tend to live along fast-flow­ing streams com­pared to low-el­e­va­tion pop­u­la­tions. Neusti­comys mon­ti­co­lus lives sym­patri­cally with other ichthy­omyine species. (E. Lee, Jr., et al., 2006; Packer and Lee, Jr., 2007; Voss, 1988)

• Habitat Regions
• tropical
• terrestrial

• Terrestrial Biomes
• rainforest
• mountains

• Aquatic Biomes
• rivers and streams

• Wetlands
• marsh

• Other Habitat Features
• riparian

• Range elevation

  1,800 to 3,754 m

  to ft

• Average elevation

  2,777 m

  ft

Phys­i­cal De­scrip­tion

Neusti­comys mon­ti­co­lus has thick, black­ish-gray pelage on its dor­sum and slightly paler pelage on its ven­ter. Sub­tle black guard hairs spo­rad­i­cally occur along the dor­sum. Neusti­comys mon­ti­co­lus has rel­a­tively large ears, rang­ing from 9 to 10 mm in length. Its tail ranges from 82 to 111 mm and is cov­ered in gray-black fur. Their vib­ris­sae range in color from black to white. Sil­very white hairs occur on the dig­its of both the fore­foot and hind­foot, which are used to dis­tin­guish N. mon­ti­co­lus from other ichthy­omyines. Slight web­bing is pre­sent be­tween the 1st in­ter­pha­langeal joints on the hind­feet. In­ter­pha­langeal web­bing and thick pelage, are spe­cial­iza­tions for swim­ming. The pelage does not change in color or tex­ture as the species ma­tures in age. Sex­ual di­mor­phism has not been doc­u­mented in this species. (An­thony, 1921; E. Lee, Jr., et al., 2006; Ochoa G. and Pas­cual, 1991; Packer and Lee, Jr., 2007; Voss, 1988)

• Other Physical Features
• endothermic
• homoiothermic
• bilateral symmetry

• Average mass

  40 g

  1.41 oz

• Range length

  192 to 223 mm

  7.56 to 8.78 in

• Average length

  208.3 mm

  8.20 in

Re­pro­duc­tion

The mat­ing sys­tem of Neusti­comys mon­ti­co­lus or its ichthy­omyine rel­a­tives has not been doc­u­mented.

Lit­tle in­for­ma­tion is avail­able re­gard­ing the re­pro­duc­tive be­hav­ior of Neusti­comys mon­ti­co­lus. It is sus­pected that in­di­vid­u­als breed dur­ing the end of the dry sea­son and be­gin­ning of the wet sea­son, which roughly spans the months of May and June. Fe­males give birth 1 to 2 off­spring per lit­ter. (Packer and Lee, Jr., 2007; Voss, 1988)

• Key Reproductive Features
• iteroparous
• seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual
• viviparous

• Breeding season

  May through June.

• Range number of offspring

  1 to 2

There is no in­for­ma­tion avail­able re­gard­ing parental care in Neusti­comys mon­ti­co­lus. As mam­mals, how­ever, fe­males ges­tate ba­bies in­ter­nally and nurse new­born young until wean­ing.

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

Lifes­pan/Longevity

There is no in­for­ma­tion avail­able re­gard­ing the life span of Neusti­comys mon­ti­co­lus.

Be­hav­ior

There is lit­tle in­for­ma­tion avail­able re­gard­ing the gen­eral be­hav­ior of Neusti­comys mon­ti­co­lus. They are noc­tur­nal and cre­pus­cu­lar, feed­ing from dusk to dawn. Neusti­comys mon­ti­co­lus is pri­mar­ily ter­res­trial and semi-na­to­r­ial. Of all ichthy­omyine species, N. mon­ti­co­lus is one of the least spe­cial­ized for swim­ming. This species is soli­tary and is only so­cial dur­ing breed­ing sea­son. (Gómez-Laverde and Del­gado, 2010; Packer and Lee, Jr., 2007; Voss, 1988)

• Key Behaviors
• terricolous
• natatorial
• nocturnal
• crepuscular
• motile
• solitary

Home Range

There is no in­for­ma­tion avail­able re­gard­ing the home range of Neusti­comys mon­ti­co­lus. (Voss, 1988)

Com­mu­ni­ca­tion and Per­cep­tion

The optic nerve of ichthy­omyine species is com­pa­ra­bly smaller than that of other muroid tribes. Thus, it is likely that Neusti­comys mon­ti­co­lus greatly de­pends on senses other than sight. It has rel­a­tively large ears, sug­gest­ing well-de­vel­oped hear­ing, and long vib­ris­sae sug­gest a de­pen­dence on hap­tic per­cep­tion. Neusti­comys mon­ti­co­lus has a set of well-de­vel­oped planter pads on the hind and fore feet, which may be im­por­tant in hap­tic per­cep­tion. (Voss, 1988)

• Communication Channels
• visual
• tactile
• acoustic

• Perception Channels
• visual
• tactile
• acoustic
• chemical

Food Habits

Neusti­comys mon­ti­co­lus is an op­por­tunis­tic feeder and for­ages on that which is im­me­di­ately and read­ily avail­able. Neusti­comys mon­ti­co­lus is pri­mar­ily in­sec­tiv­o­rous, feed­ing on in­sects and arach­nids in­clud­ing bee­tles, flies, mayflies, stone­flies, cad­dis­flies, moths and but­ter­flies, and spi­ders. Al­though stom­ach con­tent analy­sis in N. mon­ti­co­lus shows ev­i­dence for fo­livory, in­ges­tion of plant ma­te­r­ial in this species is prob­a­bly rare. (Gómez-Laverde and Del­gado, 2010; Packer and Lee, Jr., 2007; Perce­qui­llo, et al., 2005; Voss, 1988)

• Primary Diet
• carnivore
  • insectivore
  • eats non-insect arthropods

• Animal Foods
• insects
• terrestrial non-insect arthropods
• aquatic or marine worms
• aquatic crustaceans

• Plant Foods
• leaves

Pre­da­tion

There is lim­ited in­for­ma­tion re­gard­ing major preda­tors of Neusti­comys mon­ti­co­lus. Re­mains of N. mon­ti­co­lus have been dis­cov­ered in the scat of crab-eat­ing foxes. Their col­oration likely helps cam­ou­flage them from po­ten­tial preda­tors. (Del­gado-V, 2009)

• Known Predators

  • crab eating foxes (Cerdocyon thous)

Ecosys­tem Roles

Neusti­comys mon­ti­co­lus is pri­mar­ily in­sec­tiv­o­rous and may help con­trol in­sect pest pop­u­la­tions through­out their ge­o­graphic range. They are also prey for crab-eat­ing foxes and prob­a­bly a num­ber of other car­niv­o­rous mam­mals, birds, and snakes. Neusti­comys mon­ti­co­lus is gen­er­ally un­com­mon and likely has lit­tle im­pact on its local en­vi­ron­ment. (Gómez-Laverde and Del­gado, 2010; Packer and Lee, Jr., 2007; Voss, 1988)

Eco­nomic Im­por­tance for Hu­mans: Pos­i­tive

There are no known pos­i­tive ef­fects of Neusti­comys mon­ti­co­lus on hu­mans.

Eco­nomic Im­por­tance for Hu­mans: Neg­a­tive

There are no known ad­verse ef­fects of Neusti­comys mon­ti­co­lus on hu­mans.

Con­ser­va­tion Sta­tus

Neusti­comys mon­ti­co­lus is widely dis­trib­uted and abun­dant through­out its ge­o­graphic range and is clas­si­fied as a species of "least con­cern" on the IUCN's Red List of Threat­ened Species. In ad­di­tion, much of the ge­o­graphic range of N. mon­ti­co­lus is lo­cated through­out pro­tected na­tional forest­land in Ecuador and Co­lum­bia. De­for­esta­tion is a po­ten­tial threat, how­ever this has not yet be­come a major cause for con­cern. (Gómez-Laverde and Del­gado, 2010)

• IUCN Red List

  Least Concern
  More information

• IUCN Red List

  Least Concern
  More information

• US Federal List

  No special status

• CITES

  No special status

Con­trib­u­tors

Adam Glanz­man (au­thor), Uni­ver­sity of Michi­gan-Ann Arbor, Phil Myers (ed­i­tor), Uni­ver­sity of Michi­gan-Ann Arbor, John Berini (ed­i­tor), An­i­mal Di­ver­sity Web Staff.

Ref­er­ences

An­thony, 1999. Fish Eat­ing-Rats, or Aquatic Rats. Pp. 1414 in R Nowak, ed. Walker's Mam­mals of the World, Vol. Vol­ume 2, 6th Edi­tion. Bal­ti­more and Lon­don: The Johns Hop­kins Uni­ver­sity Press.

An­thony, H. 1921. Pre­lim­i­nary Re­ports on Ecuado­rian Mam­mals. No. 1. Amer­i­can Mu­seum Novi­tates, 59.9(86.6): 1-6.

Del­gado-V, C. 2009. Non-volant mam­mals, Reserva San Se­bastián-La Castel­lana, Valle de Aburrá, An­tio­quia, Colom­bia. In­sti­tuto de Bi­ología, Uni­ver­si­dad de An­tio­quia., 1: 1-4.

E. Lee, Jr., T., J. Packer, D. Al­varado-Ser­rano. 2006. Re­sults of a Mam­mal Sur­vey of the Tan­dayapa Val­ley, Ecuador. Oc­ca­sional Pa­pers, Num­ber 250: 1-8.

Gómez-Laverde, M., C. Del­gado. 2010. "Neusti­comys mon­ti­co­lus" (On-line). Home Page The IUCN Red List of Threat­ened Species. Ac­cessed April 07, 2011 at http://​www.​iucnredlist.​org/​apps/​redlist/​details/​14740/​0.

Ochoa G., J., S. Pas­cual. 1991. A New Species of Water Rat, Genus Neusti­comys An­thony, from the Andes of Venezuela. Jour­nal of Mam­mal­ogy, Vol. 72, No. 1: 97-103.

Packer, J., T. Lee, Jr.. 2007. Neusti­comys mon­ti­co­lus. Mam­malian Species, No. 805: 1-3.

Perce­qui­llo, A., A. Carmignotto,, M. Silva. 2005. A New Species of Neusti­comys (Ichthy­omyini, Sig­mod­on­ti­nae) from Cen­tral Brazil­ian Ama­zo­nia. Jour­nal of Mam­mal­ogy, Vol. 86, No. 5: 873-880.

Voss, R. 1988. SYS­TEM­AT­ICS AND ECOL­OGY OF ICHTHY­OMYINE RO­DENTS (MUROIDEA): PAT­TERNS OF MOR­PHO­LOG­I­CAL EVO­LU­TION IN A SMALL ADAP­TIVE RA­DI­A­TION. BUL­LETIN OF THE AMER­I­CAN MU­SEUM OF NAT­URAL HIS­TORY, Vol­ume 188, Ar­ti­cle 2: 262-482.