The Silver-tipped Myotis (Myotis albescens) is a species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of mouse-eared bat

Mouse-eared bat

The mouse-eared bats are a diverse and widespread genus of bats within the family Vespertilionidae.-Relationships:Myotis has historically been included in the subfamily Vespertilioninae, but was classified in its own subfamily, Myotinae, by Nancy Simmons in 1998...

 found in a range of lowland habitats in the Americas

Americas

The Americas, or America , are lands in the Western hemisphere, also known as the New World. In English, the plural form the Americas is often used to refer to the landmasses of North America and South America with their associated islands and regions, while the singular form America is primarily...

.

It is part of the Myotis genus of vesper bats, which includes a large number of common species across the world. Genetic analysis suggests that it is probably most closely related to a group of Neotropical Myotis species that includes Myotis nigricans, Myotis levis, and Myotis oxyotus, or alternatively to Myotis dominicensis alone.

Description

The silver-tipped myotis is a small bat, with a total length of 7.9 to 9.6 cm (3.1 to 3.8 ), and a tail 2.7 to 4 cm (1.1 to 1.6 ) long. The fur is long and silky, with individual hairs being black or dark brown for most of their length, but white at the tips. This silver ticking gives the bat its common name and "frosted" appearance. Although fur with a similar pattern is found on the undersides of some related species, only in the silver-tipped myotis does it extend across the entire body, thus enabling it to be distinguished from some otherwise very similar bats.

The undersides and legs of the animal are paler than the rest of the body, and the bare skin of the wings varies from light brown to almost black, depending on the individual. The bat has a rounded head with narrow, pointed ears, and unusually large feet. The membranes

Patagium

*In bats, the skin forming the surface of the wing. It is an extension of the skin of the abdomen that runs to the tip of each digit, uniting the forelimb with the body.*The patagium of a bat has four distinct parts:...

 of the wings attach to the toes at their hindmost part, while the membrane between the legs is partially supported by a long calcar

Calcar

The calcar, also known as the calcaneum , is the name given to a spur of cartilage arising from inner side of ankle and running along part of outer interfemoral membrane in bats , this is to help spread the interfemoral membrane , which is part of the wing membrane between the tail and the hind...

 that actually extends beyond its edge to end in a small rounded lump.

Distribution

The silver-tipped myotis is one of the most widespread members of its genus, being known from every country of South America except Chile

Chile

Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...

 and French Guiana

French Guiana

French Guiana is an overseas region of France, consisting of a single overseas department located on the northern Atlantic coast of South America. It has borders with two nations, Brazil to the east and south, and Suriname to the west...

. It is possible that it does occur in French Guiana, but has not yet been recorded. In the northern part of its range it is found in Panama

Panama

Panama , officially the Republic of Panama , is the southernmost country of Central America. Situated on the isthmus connecting North and South America, it is bordered by Costa Rica to the northwest, Colombia to the southeast, the Caribbean Sea to the north and the Pacific Ocean to the south. The...

, Costa Rica

Costa Rica

Costa Rica , officially the Republic of Costa Rica is a multilingual, multiethnic and multicultural country in Central America, bordered by Nicaragua to the north, Panama to the southeast, the Pacific Ocean to the west and the Caribbean Sea to the east....

, Nicaragua

Nicaragua

Nicaragua is the largest country in the Central American American isthmus, bordered by Honduras to the north and Costa Rica to the south. The country is situated between 11 and 14 degrees north of the Equator in the Northern Hemisphere, which places it entirely within the tropics. The Pacific Ocean...

, Honduras

Honduras

Honduras is a republic in Central America. It was previously known as Spanish Honduras to differentiate it from British Honduras, which became the modern-day state of Belize...

, Guatemala

Guatemala

Guatemala is a country in Central America bordered by Mexico to the north and west, the Pacific Ocean to the southwest, Belize to the northeast, the Caribbean to the east, and Honduras and El Salvador to the southeast...

, and parts of Chiapas

Chiapas

Chiapas officially Estado Libre y Soberano de Chiapas is one of the 31 states that, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided in 118 municipalities and its capital city is Tuxtla Gutierrez. Other important cites in Chiapas include San Cristóbal de las...

 and Veracruz

Veracruz

Veracruz, formally Veracruz de Ignacio de la Llave officially Estado Libre y Soberano de Veracruz de Ignacio de la Llave , is one of the 31 states that, along with the Federal District, comprise the 32 federative entities of Mexico. It is divided in 212 municipalities and its capital city is...

 in southern Mexico

Mexico

The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...

. Its wide range is partly due to a tolerance for a wide range of lowland habitats, including forests, shrublands, open wetlands, and pasture below 500 metres (1,640.4 ft) elevation. However, it usually occurs near open water. It is absent in the Andes and in the colder environments of central and southern Argentina

Argentina

Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...

.

There are no recognised subspecies.

Behavior

Like most bats, silver-tipped myotises are nocturnal, and are most active immediately after sunset and before dawn. They spend the day roosting in small groups in holes or crevices in trees or cliffs, typically close to water. They are not cave-roosting bats, preferring more open environments with some degree of ventilation and light. In more settled areas, they are commonly found roosting under roofs, or inside attic

Attic

An attic is a space found directly below the pitched roof of a house or other building . Attic is generally the American/Canadian reference to it...

 spaces. Although they may occasionally become torpid

Torpor

Torpor, sometimes called temporary hibernation is a state of decreased physiological activity in an animal, usually characterized by a reduced body temperature and rate of metabolism. Animals that go through torpor include birds and some mammals such as mice and bats...

 during cold nights, they do not hibernate.

They have been reported to feed on beetle

Beetle

Coleoptera is an order of insects commonly called beetles. The word "coleoptera" is from the Greek , koleos, "sheath"; and , pteron, "wing", thus "sheathed wing". Coleoptera contains more species than any other order, constituting almost 25% of all known life-forms...

s, flies

Fly

True flies are insects of the order Diptera . They possess a pair of wings on the mesothorax and a pair of halteres, derived from the hind wings, on the metathorax...

, lepidoptera

Lepidoptera

Lepidoptera is a large order of insects that includes moths and butterflies . It is one of the most widespread and widely recognizable insect orders in the world, encompassing moths and the three superfamilies of butterflies, skipper butterflies, and moth-butterflies...

ns, and spider

Spider

Spiders are air-breathing arthropods that have eight legs, and chelicerae with fangs that inject venom. They are the largest order of arachnids and rank seventh in total species diversity among all other groups of organisms...

s. They are generally slow flying bats, flying low to the ground or water, and grabbing insects with their large feet. While hunting, they have been reported to use short, 2 to 5 millisecond, frequency modulated calls, sweeping down from 75 to 43 kHz, at sound levels of up to at least 111 dB

Decibel

The decibel is a logarithmic unit that indicates the ratio of a physical quantity relative to a specified or implied reference level. A ratio in decibels is ten times the logarithm to base 10 of the ratio of two power quantities...

.

Reproduction

Males and females roost together, and the females are promiscuous, mating with several of their partners. There is no particular breeding season over most parts of the range, and females typically give birth to two or three young every year. Fertilisation does not occur for up to three months after mating indicating that females can likely store sperm in their bodies for this time, thus being able to control the timing of their pregnancy. Gestation

Gestation

Gestation is the carrying of an embryo or fetus inside a female viviparous animal. Mammals during pregnancy can have one or more gestations at the same time ....

 lasts about three months, and results in the birth of a single young.

The young are weaned

Weaning

Weaning is the process of gradually introducing a mammal infant, either human or animal, to what will be its adult diet and withdrawing the supply of its mother's milk.The process takes place only in mammals, as only mammals produce milk...

 at about one month of age, by which time all their permanent teeth

Permanent teeth

Permanent teeth are the second set of teeth formed in humans. There are thirty-two permanent teeth, consisting of six maxillary and six mandibular molars, four maxillary and four mandibular premolars, two maxillary and two mandibular canines, four maxillary and four mandibular incisors.The first...

have erupted. Females become sexually mature at just two months, although males are not fertile for six or seven months after birth.