Cryptotis meridensis

Geographic Range

Cryptotis meridensis occurs only in the states of Trujillo, Me’rida, and eastern Ta’chira, Venezuela. Within these states, C. meridensis is endemic to the Cordillera de los Andes.

• Biogeographic Regions
• neotropical neotropical
  • native native

Habitat

An inhabitant of the cloud forest and pa’ramo vegetation types, Cryptotis meridensis can be found in montane forests with moderate to high levels of moisture, such as montane rain forests. It can also be found in subalpine pa´ramo and stands of of Polylepis and Espeletia tree species surrounded by pa’ramo at high elevations in the South American Andes.

Merida small-eared shrews are found over a broad range of elevations and associated habitats. They occur at elevations of 800 to 1,700 meters, where forest is seasonal, canopy height measures 20 to 25 meters, epiphytes and lianas are few in number, and there is a regular dry season lasting a from 1 to 3 months. At elevations of 1,700 to 3,000 meters, small-eared shrews occur in cloud forest vegetation types with a canopy height measuring 25 to 35 meters and an average annual precipitation of 1,000 to 2,600 millimeters. Evergreen dry forest is an additional vegetation assemblage within which C. meridensis occurs, provided an elevation of 1,600 to 2,700 meters, a canopy height reaching 3 to 5 meters, and an average annual precipitation of 500 to 1,000 millimeters. Where elevations range from 2,800 to 4,000 meters, this species largely occurs in pa’ramo. Andean pa’ramo hosting small-eared shrews has a maximum canopy height of 0.5 to 4.0 meters, tremendous temperature fluctuations, and an annual average precipitation of 450 to 550 millimeters.

Within elevation, canopy height, and annual average precipitation restrictions, Cryptotis meridensis occupies closed-canopy habitat in cloud forest, secondary scrub bordering streams, and open pa’ramo. Due to its ability to tolerate a considerable degree of environmental disturbance, small-eared shrews are also able to occupy forest stands disturbed by burning, as well as stands that represent disturbed transitions between cloud forest and pa’ramo. C. meridensis densities increase with increased leaf litter, and increased densities of ferns, palms, creepers, and trees. Increased canopy cover and tree diameter also have a positive effect on the presence of this species.

• Habitat Regions
• tropical tropical
• terrestrial terrestrial

• Terrestrial Biomes
• forest forest
• rainforest rainforest
• scrub forest scrub forest
• mountains mountains

Physical Description

As the largest shrew species in its genus, Cryptotis meridensis has a head and body length ranging from 70 to 102 millimeters, with an average head and body length of 88 millimeters. It has a long tail that measures from 25 to 41 millimeters in length, with an average of 33 millimeters. Total length, including head, body, and tail of C. meridensis , ranges from 100 to 135 millimeters and averages 122 millimeters. Cryptotis meridensis weighs from 8.5 to 18 grams, with an average weight of 12.3 grams. Dorsal pelage is thick and measures 4 to 6 millimeters in length. The chocolate brown dorsum stands in sharp contrast to its olive brown venter, which appears pale in comparison. The forepaws are enlarged and the foreclaws elongated. Males and females of this species are very similar in appearance and are difficult to distinguish using external characteristics.

• Other Physical Features
• endothermic endothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• sexes alike

Reproduction

The mating behavior of Cryptotis meridensis has not been described. However its close relative, Cryptotis parva , is known to exhibit polygamy.

Little information is available concerning the reproductive behavior of Cryptotis meridensis . Trapping data from a number of sites suggest two reproductive periods. The first breeding season appears to be restricted to March and April. The second breeding season, however, appears more variable in timing, with breeding occurring between the months of July and December. Small-eared shrews of the Monte Zerpa cloud forest appear to breed on a year-round basis. Regardless of breeding season, C. meridensis usually has 3 pups per litter.

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

There is no information available regarding parental investment in Cryptotis meridensis . However, females of a closely related species, Cryptotis parva , nurse pups for nearly a month, and young stay in close contact with their mother for 20 to 23 days. If pups become separated from their mother prior to weaning, the mother exhibits behaviors suggesting panic until she is able to locate all of her pups.

Lifespan/Longevity

No information is available regarding the lifespan of Cryptotis meridensis , but a close relative, Cryptotis parva , is thought to live for about 18 months in the wild and is known to survive 33 months in captivity.

Behavior

Little information is available regarding the general behavior of Cryptotis meridensis . It is mostly, if not completely, terrestrial and develops tunnel systems and nests that are actively built by this species. In fact, for C. meridensis to occur in pa’ramo, there must be an extensive, thick layer of mosses and lichens present for tunnel and nest building activities. Similarly, leaf litter, rocks, and fallen trees provide essential habitat for C. meridensis in cloud forest.

• Key Behaviors
• terricolous
• fossorial fossorial
• motile motile

Home Range

The home range of Cryptotis meridensis is unknown. However, the closely related Cryptotis parva maintains a home range of approximately 2000 m^2. Within its home range, C. parva actively defends its nest, but not the rest of the home range.

Communication and Perception

The eyes and ears of Cryptotis meridensis are significantly reduced compared to other mammals in its size range. Communication in this species relies largely on its to sense its surroundings through use of vibrissae and olfaction. Like other shrews of the genus Cryptotis , small-eared shrews have vibrissae on their face. In addition to vibrissae, C. meridensis depends on its sense of smell to perceive their immediate environment.

• Communication Channels
• tactile tactile
• chemical chemical

• Perception Channels
• tactile tactile
• chemical chemical

Food Habits

Hypogeal or underground invertebrates account for over half the diet of small-eared shrews. Of these invertebrates, beetle larvae, cockroaches , earthworms , fly larvae, isopods , snails , and moth larvae and pupae are commonly consumed. Epigeal or surface-dwelling prey account for a smaller portion of the shrew’s diet. Such prey includes crickets , grasshoppers , and spiders . Cosmopolitan prey is also included in the diet of Cryptotis meridensis . However, cosmopolitan prey represents a considerably smaller portion of its diet than do other prey categories. In fact, based on studies of the small-eared shrew, hypogeal prey represents 69.4 percent of prey items, epigeal prey represents 27.2 percent of prey items, and cosmopolitan prey represents only 3.4 percent of prey items. Small-eared shrews have also been known to consume less common prey items, including nestling rodents , lizards , and the eggs and chicks of ground-nesting birds .

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

• Animal Foods
• birds
• mammals
• reptiles
• eggs
• insects
• terrestrial non-insect arthropods
• mollusks
• terrestrial worms

Predation

Barn owls are the primary predator of Cryptotis meridensis . Other predators include black-and-white hawk-eagles , white-rumped hawks , white-eared opossums , southern opossums , long-tailed weasels , and mountain coatis .

Ecosystem Roles

Cryptotis meridensis is prey for a number of differnt bird and mammals species throughout its geographic range. In turn, small-eared shrews commonly act as predators on a large variety invertebrates. To a lesser extent, C. meridensis preys on nestling rodents , lizards , and the eggs and chicks of ground-nesting birds .

Cryptotis meridensis is host to a variety of parasites. Both the laelapid mite and two species of trombiculid chiggers, Eutrombicula wolfenbargeri and Hoffmannina mahuens , are ectoparasites that take common in C. meridensis . Ticks are also commonly associated with C. meridensis .

Economic Importance for Humans: Positive

There are no known positive effects of Cryptotis meridensis on humans.

Economic Importance for Humans: Negative

There are no known adverse effects of Cryptotis meridensis on humans.

Conservation Status

Cryptotis meridensis is classified as a species of "least concern" on the IUCN's Red List of Threatened Species. In cloud forest and pa’ramo habitat, small-eared shrews are one of the most common small mammal species and are even found in association with disturbed and secondary scrub habitats. However, because it is endemic to the high-altitude Andes of only a handful of states in South America, C. meridensis is recognized as a “susceptible” species. This susceptibility increases as its high-altitude habitats become increasingly fragmented.

Other Comments

The binomial name " Cryptotis meridensis " is derived from Greek and Latin. " Crypt(os) " is Greek for “hidden” or “concealed” and " otis " is Greek for “eared creature.” The species epithet, " meridensis ", comes from Me’rid(a) and ensis , a Latin suffix indicative of place. Together, the two portions of the species epithet are a reference to the type locality of small-eared shrews.

Additional Links

Encyclopedia of Life

Contributors

Ashley Potter (author), Michigan State University, Barbara Lundrigan (editor), Michigan State University, John Berini (editor), Animal Diversity Web Staff.

References

Baker, R. 1991. Michigan Mammals . East Lansing: Michigan State University Press.

Choate, J., J. Jones, C. Jones. 1994. Handbook Of Mammals of the South-Central States . Baton Rouge and London: Louisiana State University Press.

Schwartz, C., E. Schwartz. 1981. The Wild Mammals of Missouri . Columbia & London: University of Missouri Press and Missouri Department of Conservation.

Whitaker, J. 1974. Cryptotis parva . Mammalian Species , 43: 1-8.

Woodman, N., A. Diaz de Pascual. 2004. Cryptotis meridensis . Mammalian Species , 761: 1-5.

Woodman, N. 2002. A new species of small-eared shrew from Colombia and Venezuela (Mammalia: Soricomorpha: Soricidae: Genus Cryptotis ). Proceedings of the Biological Society of Washington , 115/2: 249-272.