Geographic Range
Phyllotis amicus
is found exclusively on the coast and lower Pacific slopes of western Peru stretching
from Piura to Arequipa.
- Biogeographic Regions
- neotropical
Habitat
Phyllotis amicus
occurs in xeric, arid environments wish sparse vegetative cover. The habitat varies
from dry, rocky slopes with boulders to sandy areas with
Capparis
bushes and mesquite to steep rocky hillsides with scattered shrub and cacti cover.
The friendly leaf-eared mouse has also been found to occur in dry slopes dominated
by boulders and tola bushes. The elevation which
P. amicus
occurs ranges from 50-2,100 m.
A 2002 study discovered that
P. amicus
can be found in a unique seasonal habitat on the central coast of Peru , 105 km north
of Lima, the Lomas of Lachay. Mean annual precipitation in this area is .5mm. This
habitat is harsh, xeric environment.
- Habitat Regions
- terrestrial
- Terrestrial Biomes
- desert or dune
Physical Description
Phyllotis amicus
is characterized by small body size, ears as long as or longer than hind feet, short
molar toothrows (3.5-4.2mm), and short hind feet. The friendly leaf-eared mouse typically
has short brown fur and a naked tail. The underbelly and tail are pure white. Specimens
at the costal, Northern-most part of its range are small and brightly colored. As
the range progresses south and inland, specimens become larger and duller. The interorbital
region of
P. amicus
is broad and flat and the edges are frequently square or sharp. The skull also presents
large and globular auditory bullae. This species has opisthodont upper incisors and
a conspicuous development of second out entrant angle on M2.
The range of
Phyllotis amicus
comes in contact with
P. limatus
,
P. andium
,
P. definitus
, and
P. gerbillus
.
P. amicus
is much smaller than
P. definitus
and
P. limatus
and has shorter fur, a more naked tail, smaller teeth, opisthodont incisors, and
a more conspicuous development of two outer entrant angles of M2.
P. amicus
can be distinguished from
P. gerbillus
with its pure white belly and tail, and smaller ears.
P. amicus
is smaller, slightly paler, has a more conspicuous development of second out entrant
angle on M2, and ears proportionally larger than
P. andium
.
- Other Physical Features
- endothermic
- bilateral symmetry
- Sexual Dimorphism
- sexes alike
Reproduction
There is little available information on the mating systems of Phyllotis amicus .
The species
Phyllotis amicus
displays no seasonal reproductive activity and has been found to reproduce year-round.
Lack of seasonal reproduction may be tied to the feeding habits of the species. It
is possible that
P. amicus
has a lower dependence on availability of vegetation, unlike the other
Phyllotis
species, because they have been found to consume more insects than any other species
of
Phyllotis
.
Friendly leaf-eared mice have a gestation period of 24 days and have a litter size
of 1-3. A smaller litter size provides greater potential survivorship in a harsh xeric
environment than a large litter. A 2002 study found a significant difference between
weight and age with different litter sizes of
P. amicus
which indicated a relationship between weight and litter size. Young from a litter
of 2 were found to get heavier and gain weight faster than young from a larger litter.
The short duration of
P. amicus
pregnancy suggests that a female can reproduce many times in one year.
There is not much documentation about what age
Phyllotis amicus
becomes sexually mature, however in captivity it was found that females less than
7 months old were not reproductive.
Young
P. amicus
are weaned at 30 days of age. The mean weight at weaning is 14.4g(+-)2.6g. Young
reach their mean weight of 20.8g(+-) 4.7g at 2-3 months of age.
- Key Reproductive Features
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
There is little known information on the parental investment of
Phyllotis amicus
. In captivity, females raise their young without the presence of the father. Young
are weaned at 30 days of age.
- Parental Investment
- female parental care
-
pre-weaning/fledging
-
provisioning
- female
-
protecting
- female
-
provisioning
Lifespan/Longevity
There is little available information regarding the lifespan of Phyllotis amicus .
Behavior
Phyllotis amicus
is a nocturnal species. Not much is known about its social behavior, however it is
thought that the species could have a social type of spatial organization due to its
aggregated distribution throughout the year. This may be the result of a limiting
factor such as shelter or substrate.
- Key Behaviors
- motile
Home Range
There is little information known about the home range of
Phyllotis amicus
however in a 2002 study it was found that
P. amicus
moved 22.8-77.8m per month with a mean movement of 44.5m.
Communication and Perception
Little is known about the communication and perception of Phyllotis amicus
Food Habits
Although limited information is available on the diet of
Phyllotis amicus
, it is known that this species is omnivorous and consumes more insects than other
Phyllotis
species. The feeding habits of
P. amicus
imply that this species may depend less on availability of vegetation and as a consequence,
allows this species to reproduce without seasonality. In captivity,
P. amicus
consumes fresh carrots, lettuce, sweet potato, sprouted wheat, and corn.
P. amicus
has been found to not drink water in captivity which implies that the species has
the capacity to survive through a drought.
- Animal Foods
- insects
- Plant Foods
- leaves
- roots and tubers
- seeds, grains, and nuts
Predation
Little information is known about the depredation of
Phyllotis amicus
. The species
P. amicus
does, however, occur in similar areas to another
Phyllotis
species,
Phyllotis darwini
. Burrowing owls (
Athene cunicularia
), barn owls (
Tyto alba
), and Culpeo foxes (
Lycalopex culpaeus
) are known predators of
P. darwini
.
Ecosystem Roles
Little is known about the ecosystem role of
Phyllotis amicus
. The friendly leaf eared mouse is predator to insects in its region and potentially
prey to burrowing owls (Athene cunicularia), barn owls (Tyto alba), and Culpeo foxes
(Lycalopex culpaeus).
Economic Importance for Humans: Positive
There is little known information on the positive economic importance of
Phyllotis amicus
to humans, however this species is easy to keep in captivity which could imply their
use for research.
Economic Importance for Humans: Negative
There is little known information on the negative economic importance of
Phyllotis amicus
to humans however, this species does consume both grains and insects which could
impact farming within this species' range.
Conservation Status
Phyllotis amicus
is listed as a species of Least Concern on the ICUN Red List and is not listed on
the US Federal List, CITES, or the State of Michigan List. The friendly leaf-eared
mouse has a wide distribution, with a population density of 0 to 12 individuals per
hectare and occurs in a number of protected areas.
Additional Links
Contributors
Margaret Braun (author), University of Wisconsin Stevens Point, Christopher Yahnke (editor), University of Wisconsin-Stevens Point, Tanya Dewey (editor), University of Michigan-Ann Arbor.
- Neotropical
-
living in the southern part of the New World. In other words, Central and South America.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- terrestrial
-
Living on the ground.
- desert or dunes
-
in deserts low (less than 30 cm per year) and unpredictable rainfall results in landscapes dominated by plants and animals adapted to aridity. Vegetation is typically sparse, though spectacular blooms may occur following rain. Deserts can be cold or warm and daily temperates typically fluctuate. In dune areas vegetation is also sparse and conditions are dry. This is because sand does not hold water well so little is available to plants. In dunes near seas and oceans this is compounded by the influence of salt in the air and soil. Salt limits the ability of plants to take up water through their roots.
- female parental care
-
parental care is carried out by females
- carnivore
-
an animal that mainly eats meat
- insectivore
-
An animal that eats mainly insects or spiders.
- omnivore
-
an animal that mainly eats all kinds of things, including plants and animals
- endothermic
-
animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.
- bilateral symmetry
-
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
- sexual
-
reproduction that includes combining the genetic contribution of two individuals, a male and a female
- motile
-
having the capacity to move from one place to another.
- tactile
-
uses touch to communicate
- chemical
-
uses smells or other chemicals to communicate
References
Arana, M., O. Ramirez, S. Santa Maria, C. Kunimoto, R. Velarde, C. De La Cruz, M. Luisa Ruiz. 2002. Population density and reproduction of two Peruvian leaf-eared mice ( Phyllotis spp.). Revista Chilena de Historia Natural , 75: 751-756.
Patton, J. 2015. Mammals of South America, Volume 2: Rodents . Chicago, Illinois, USA: University of Chicago Press.
Pearson, O. 1972. New informtion on ranges and relationships within the rodent genus Phyllotis in Peru and Ecuador. Journal of Mammalogy , 53: 677-686.
Pizzimenti, J., R. De Salle. 1980. Dietary and morphometric variation in some Peruvian rodent communities: the effect of feeding strategy on evolution. Biological Journal of the Linnean Society , 13: 263-285.
Previtali, M., M. Lima, P. Meserve, D. Kelt, J. Gutierrez. 2009. Population dynamics of two sympatric rodents in a variable environment: rainfall, resource availability, and predation. Ecology , 90/7: 1996-2006.
2016. "Phyllotis amicus" (On-line). The ICUN Red List of Threatened Species. Accessed August 20, 2016 at http://www.iucnredlist.org/details/17220/0 .