Short-eared Dog
Encyclopedia
The short-eared dog also known as the short-eared fox or the short-eared zorro, is a unique and elusive canid species
endemic to the Amazonian
basin
. This is the only species
assigned to the genus
Atelocynus.
ns and many of the other terrestrial placental mammals of South America
. After the formation of the Isthmus of Panama
in the latter part the Tertiary
(about 2.5 million years ago in the Pliocene
), dogs migrated from North America to the southern continent as part of the Great American Interchange
. The short-eared dog's ancestors adapted to life in tropical rainforest
s, developing the requisite morphological and anatomical features. Apart from its superficial resemblance to the bush dog
, the short-eared dog seems not to be closely related to any fox-like or wolf-like canid (R. Burton; International Wildlife Encyclopedia, 2002). It is one of the most unusual canids. The latest systematics
classifies it as a species in the tribe
Canini
, and its closest extant relative is probably the distant taxon, the Crab-eating Fox
(Cerdocyon thous)(Pietrzak, 2007). It has 74 chromosomes (2 x 36 autosomes + one pair of sex chromosomes).
Two subspecies of this canid are recognized:
region of South America
(in Peru
, Bolivia
, Brazil
, Colombia
, Ecuador
and possible Venezuela
). It lives in various parts of the rainforest environment, preferring areas with little human disturbance. It lives in both lowland forests known as Selva Amazónica
and terra firme forest
, as well as in swamp forest
, stands of bamboo
, and cloud forest
.
s with short and rounded ears. The short-eared dog has a distinctive fox-like muzzle and bushy tail. It ranges from dark to reddish-grey, but can also be nearly navy blue, coffee brown, dark grey or chestnut-grey until to black, and the coat is short, with thick and bristly fur. Its paw
s are partly webbed, owing to its partly aquatic habitat.
It moves with feline lightness unparalleled among the other canids. It has a somewhat narrow chest, with dark color variation on thorax merging to brighter, more reddish tones on the abdominal side of the body. This species possesses a large elongated head and long canine teeth, protruding even when its muzzle
is closed. Its back often has a dark streak, while a brighter stain is on its tail. Like all canids, it has 42 teeth.
Typical height at the shoulder is 25–30 cm. Its head and body length is about 100 cm, with a tail of about 30–35 cm. It weighs about 9–10 kg.
, with fish
, insect
s, and small mammal
s making up the majority of its diet. An investigation led in Cocha Cashu Biological Station
in Peru
into the proportions of different kinds of food in this animal's diet produced the following results: fish 28%, insects 17%, small mammals 13%, various fruit
s 10%, crab
s 10%, frog
s 4%, reptile
s 3%, bird
s 10%.
s of this species are about almost 1/3 larger than male
s. The excited male sprays a musk
produced by the tail glands. It prefers a solitary lifestyle, in forest areas. It avoids humans in the natural environment
. Agitated males will raise the hairs on their backs.
Lifespan and gestation period
are unknown, although it is assumed that sexual maturity
is reached at about one year of age.
, Cougar, Ocelot
, Margay
and Giant Otter
, and competes for territory with the Bush Dog
.
Feral
dog
s pose a prominent threat to the population of short-eared dogs, as they facilitate the spread of diseases such as canine distemper
and rabies
to the wild population. Humans also contribute to the extermination of the short-eared dog via degradation of the species' natural habitat and the destruction of tropical rainforests
. Scientists still have little knowledge of its biology.
by IUCN. There is not any comprehensive ecological and genetic research carried out on the species.
are recognized:
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...
endemic to the Amazonian
Amazon River
The Amazon of South America is the second longest river in the world and by far the largest by waterflow with an average discharge greater than the next seven largest rivers combined...
basin
Drainage basin
A drainage basin is an extent or an area of land where surface water from rain and melting snow or ice converges to a single point, usually the exit of the basin, where the waters join another waterbody, such as a river, lake, reservoir, estuary, wetland, sea, or ocean...
. This is the only species
Monotypic
In biology, a monotypic taxon is a taxonomic group with only one biological type. The term's usage differs slightly between botany and zoology. The term monotypic has a separate use in conservation biology, monotypic habitat, regarding species habitat conversion eliminating biodiversity and...
assigned to the genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
Atelocynus.
Other names
It has many names in the indigenous languages where it is endemic, such as: cachorro-do-mato-de-orelha-curta in Portuguese, zorro de oreja corta in Spanish, nomensarixi in the Chiquitano language, and uálaca in Yucuna. Other names in Spanish are zorro ojizarco, zorro sabanero, zorro negro.Evolution and systematics
The short-eared dog's history is similar to that of the other carnivoraCarnivora
The diverse order Carnivora |Latin]] carō "flesh", + vorāre "to devour") includes over 260 species of placental mammals. Its members are formally referred to as carnivorans, while the word "carnivore" can refer to any meat-eating animal...
ns and many of the other terrestrial placental mammals of South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
. After the formation of the Isthmus of Panama
Isthmus of Panama
The Isthmus of Panama, also historically known as the Isthmus of Darien, is the narrow strip of land that lies between the Caribbean Sea and the Pacific Ocean, linking North and South America. It contains the country of Panama and the Panama Canal...
in the latter part the Tertiary
Tertiary
The Tertiary is a deprecated term for a geologic period 65 million to 2.6 million years ago. The Tertiary covered the time span between the superseded Secondary period and the Quaternary...
(about 2.5 million years ago in the Pliocene
Pliocene
The Pliocene Epoch is the period in the geologic timescale that extends from 5.332 million to 2.588 million years before present. It is the second and youngest epoch of the Neogene Period in the Cenozoic Era. The Pliocene follows the Miocene Epoch and is followed by the Pleistocene Epoch...
), dogs migrated from North America to the southern continent as part of the Great American Interchange
Great American Interchange
The Great American Interchange was an important paleozoogeographic event in which land and freshwater fauna migrated from North America via Central America to South America and vice versa, as the volcanic Isthmus of Panama rose up from the sea floor and bridged the formerly separated continents...
. The short-eared dog's ancestors adapted to life in tropical rainforest
Rainforest
Rainforests are forests characterized by high rainfall, with definitions based on a minimum normal annual rainfall of 1750-2000 mm...
s, developing the requisite morphological and anatomical features. Apart from its superficial resemblance to the bush dog
Bush Dog
The bush dog is a canid found in Central and South America, including Panama, Colombia, Venezuela, Bolivia, Peru , Ecuador, the Guianas, Paraguay, northeast Argentina and Brazil...
, the short-eared dog seems not to be closely related to any fox-like or wolf-like canid (R. Burton; International Wildlife Encyclopedia, 2002). It is one of the most unusual canids. The latest systematics
Systematics
Biological systematics is the study of the diversification of terrestrial life, both past and present, and the relationships among living things through time. Relationships are visualized as evolutionary trees...
classifies it as a species in the tribe
Tribe (biology)
In biology, a tribe is a taxonomic rank between family and genus. It is sometimes subdivided into subtribes.Some examples include the tribes: Canini, Acalypheae, Hominini, Bombini, and Antidesmeae.-See also:* Biological classification* Rank...
Canini
Canini
Canini may refer to:A notable Italian surname* Angelo Canini, Italian grammarian* Giovanni Angelo Canini, Italian painter and engraver* Marcantonio Canini, Italian painter and sculptor* Michele Canini, Italian footballer...
, and its closest extant relative is probably the distant taxon, the Crab-eating Fox
Crab-eating Fox
The crab-eating fox , also known as the forest fox, wood fox, and the common fox, is an extant species of medium-sized canid endemic to the central part of South America and which appeared during the Pliocene epoch...
(Cerdocyon thous)(Pietrzak, 2007). It has 74 chromosomes (2 x 36 autosomes + one pair of sex chromosomes).
Two subspecies of this canid are recognized:
- Atelocynus microtis microtis
- Atelocynus microtis sclateri
Occurrence and environment
The short-eared dog can be found in the Amazon rainforestAmazon Rainforest
The Amazon Rainforest , also known in English as Amazonia or the Amazon Jungle, is a moist broadleaf forest that covers most of the Amazon Basin of South America...
region of South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
(in Peru
Peru
Peru , officially the Republic of Peru , is a country in western South America. It is bordered on the north by Ecuador and Colombia, on the east by Brazil, on the southeast by Bolivia, on the south by Chile, and on the west by the Pacific Ocean....
, Bolivia
Bolivia
Bolivia officially known as Plurinational State of Bolivia , is a landlocked country in central South America. It is the poorest country in South America...
, Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
, Colombia
Colombia
Colombia, officially the Republic of Colombia , is a unitary constitutional republic comprising thirty-two departments. The country is located in northwestern South America, bordered to the east by Venezuela and Brazil; to the south by Ecuador and Peru; to the north by the Caribbean Sea; to the...
, Ecuador
Ecuador
Ecuador , officially the Republic of Ecuador is a representative democratic republic in South America, bordered by Colombia on the north, Peru on the east and south, and by the Pacific Ocean to the west. It is one of only two countries in South America, along with Chile, that do not have a border...
and possible Venezuela
Venezuela
Venezuela , officially called the Bolivarian Republic of Venezuela , is a tropical country on the northern coast of South America. It borders Colombia to the west, Guyana to the east, and Brazil to the south...
). It lives in various parts of the rainforest environment, preferring areas with little human disturbance. It lives in both lowland forests known as Selva Amazónica
Amazon Rainforest
The Amazon Rainforest , also known in English as Amazonia or the Amazon Jungle, is a moist broadleaf forest that covers most of the Amazon Basin of South America...
and terra firme forest
Tropical and subtropical moist broadleaf forests
Tropical and subtropical moist broadleaf forests , also known as tropical moist forests, are a tropical and subtropical forest biome....
, as well as in swamp forest
Freshwater swamp forest
Freshwater swamp forests, or flooded forests, are forests which are inundated with freshwater, either permanently or seasonally. They normally occur along the lower reaches of rivers and around freshwater lakes...
, stands of bamboo
Tropical and subtropical moist broadleaf forests
Tropical and subtropical moist broadleaf forests , also known as tropical moist forests, are a tropical and subtropical forest biome....
, and cloud forest
Cloud forest
A cloud forest, also called a fog forest, is a generally tropical or subtropical evergreen montane moist forest characterized by a persistent, frequent or seasonal low-level cloud cover, usually at the canopy level. Cloud forests often exhibit an abundance of mosses covering the ground and...
.
Appearance
The short-eared dog has short and slender limbLimb (anatomy)
A limb is a jointed, or prehensile , appendage of the human or other animal body....
s with short and rounded ears. The short-eared dog has a distinctive fox-like muzzle and bushy tail. It ranges from dark to reddish-grey, but can also be nearly navy blue, coffee brown, dark grey or chestnut-grey until to black, and the coat is short, with thick and bristly fur. Its paw
Paw
A paw is the soft foot of a mammal, generally a quadruped, that has claws or nails. A hard foot is called a hoof. Paws are used to pad feet for walking and increase friction.- Common characteristics :...
s are partly webbed, owing to its partly aquatic habitat.
It moves with feline lightness unparalleled among the other canids. It has a somewhat narrow chest, with dark color variation on thorax merging to brighter, more reddish tones on the abdominal side of the body. This species possesses a large elongated head and long canine teeth, protruding even when its muzzle
Snout
The snout, or muzzle, is the protruding portion of an animal's face, consisting of its nose, mouth, and jaw.-Terminology:The term "muzzle", used as a noun, can be ambiguous...
is closed. Its back often has a dark streak, while a brighter stain is on its tail. Like all canids, it has 42 teeth.
Typical height at the shoulder is 25–30 cm. Its head and body length is about 100 cm, with a tail of about 30–35 cm. It weighs about 9–10 kg.
Diet
This wild dog is mainly a carnivoreCarnivore
A carnivore meaning 'meat eater' is an organism that derives its energy and nutrient requirements from a diet consisting mainly or exclusively of animal tissue, whether through predation or scavenging...
, with fish
Fish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...
, insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...
s, and small mammal
Mammal
Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...
s making up the majority of its diet. An investigation led in Cocha Cashu Biological Station
Cocha Cashu Biological Station
Cocha Cashu Biological Station is a tropical biological research station located at 11° 54'S and 71° 22'W in Manú National Park, Peru. It was established in 1969-70, predating the founding of its containing national park . Though only 10 km2 in area, the site has provided valuable research...
in Peru
Peru
Peru , officially the Republic of Peru , is a country in western South America. It is bordered on the north by Ecuador and Colombia, on the east by Brazil, on the southeast by Bolivia, on the south by Chile, and on the west by the Pacific Ocean....
into the proportions of different kinds of food in this animal's diet produced the following results: fish 28%, insects 17%, small mammals 13%, various fruit
Fruit
In broad terms, a fruit is a structure of a plant that contains its seeds.The term has different meanings dependent on context. In non-technical usage, such as food preparation, fruit normally means the fleshy seed-associated structures of certain plants that are sweet and edible in the raw state,...
s 10%, crab
Crab
True crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" , or where the reduced abdomen is entirely hidden under the thorax...
s 10%, frog
Frog
Frogs are amphibians in the order Anura , formerly referred to as Salientia . Most frogs are characterized by a short body, webbed digits , protruding eyes and the absence of a tail...
s 4%, reptile
Reptile
Reptiles are members of a class of air-breathing, ectothermic vertebrates which are characterized by laying shelled eggs , and having skin covered in scales and/or scutes. They are tetrapods, either having four limbs or being descended from four-limbed ancestors...
s 3%, bird
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
s 10%.
Reproduction and behavior
This species has some unique behaviors not typical to other canids. FemaleFemale
Female is the sex of an organism, or a part of an organism, which produces non-mobile ova .- Defining characteristics :The ova are defined as the larger gametes in a heterogamous reproduction system, while the smaller, usually motile gamete, the spermatozoon, is produced by the male...
s of this species are about almost 1/3 larger than male
Male
Male refers to the biological sex of an organism, or part of an organism, which produces small mobile gametes, called spermatozoa. Each spermatozoon can fuse with a larger female gamete or ovum, in the process of fertilization...
s. The excited male sprays a musk
Musk
Musk is a class of aromatic substances commonly used as base notes in perfumery. They include glandular secretions from animals such as the musk deer, numerous plants emitting similar fragrances, and artificial substances with similar odors. Musk was a name originally given to a substance with a...
produced by the tail glands. It prefers a solitary lifestyle, in forest areas. It avoids humans in the natural environment
Natural environment
The natural environment encompasses all living and non-living things occurring naturally on Earth or some region thereof. It is an environment that encompasses the interaction of all living species....
. Agitated males will raise the hairs on their backs.
Lifespan and gestation period
Gestation period
For mammals the gestation period is the time in which a fetus develops, beginning with fertilization and ending at birth. The duration of this period varies between species.-Duration:...
are unknown, although it is assumed that sexual maturity
Sexual maturity
Sexual maturity is the age or stage when an organism can reproduce. It is sometimes considered synonymous with adulthood, though the two are distinct...
is reached at about one year of age.
Threats, survival and ecological concerns
The short-eared dog competes for food with the JaguarJaguar
The jaguar is a big cat, a feline in the Panthera genus, and is the only Panthera species found in the Americas. The jaguar is the third-largest feline after the tiger and the lion, and the largest in the Western Hemisphere. The jaguar's present range extends from Southern United States and Mexico...
, Cougar, Ocelot
Ocelot
The ocelot , pronounced /ˈɒsəˌlɒt/, also known as the dwarf leopard or McKenney's wildcat is a wild cat distributed over South and Central America and Mexico, but has been reported as far north as Texas and in Trinidad, in the Caribbean...
, Margay
Margay
The Margay is a spotted cat native to Middle and South America. Named for Prince Maximilian of Wied-Neuwied, it is a solitary and nocturnal animal that prefers remote sections of the rainforest. Although it was once believed to be vulnerable to extinction, the IUCN now lists it as "Near Threatened"...
and Giant Otter
Giant Otter
The giant otter is a South American carnivorous mammal. It is the longest member of the Mustelidae, or weasel family, a globally successful group of predators. Unusually for a mustelid, the giant otter is a social species, with family groups typically supporting three to eight members...
, and competes for territory with the Bush Dog
Bush Dog
The bush dog is a canid found in Central and South America, including Panama, Colombia, Venezuela, Bolivia, Peru , Ecuador, the Guianas, Paraguay, northeast Argentina and Brazil...
.
Feral
Feral
A feral organism is one that has changed from being domesticated to being wild or untamed. In the case of plants it is a movement from cultivated to uncultivated or controlled to volunteer. The introduction of feral animals or plants to their non-native regions, like any introduced species, may...
dog
Dog
The domestic dog is a domesticated form of the gray wolf, a member of the Canidae family of the order Carnivora. The term is used for both feral and pet varieties. The dog may have been the first animal to be domesticated, and has been the most widely kept working, hunting, and companion animal in...
s pose a prominent threat to the population of short-eared dogs, as they facilitate the spread of diseases such as canine distemper
Canine distemper
Canine distemper is a viral disease that affects animals in the families Canidae, Mustelidae, Mephitidae, Hyaenidae, Ailuridae, Procyonidae, Pinnipedia, some Viverridae and Felidae...
and rabies
Rabies
Rabies is a viral disease that causes acute encephalitis in warm-blooded animals. It is zoonotic , most commonly by a bite from an infected animal. For a human, rabies is almost invariably fatal if post-exposure prophylaxis is not administered prior to the onset of severe symptoms...
to the wild population. Humans also contribute to the extermination of the short-eared dog via degradation of the species' natural habitat and the destruction of tropical rainforests
Tropical rainforest
A tropical rainforest is an ecosystem type that occurs roughly within the latitudes 28 degrees north or south of the equator . This ecosystem experiences high average temperatures and a significant amount of rainfall...
. Scientists still have little knowledge of its biology.
Status of conservation
The short-eared dog is currently considered near threatenedNear Threatened
Near Threatened is a conservation status assigned to species or lower taxa that may be considered threatened with extinction in the near future, although it does not currently qualify for the threatened status...
by IUCN. There is not any comprehensive ecological and genetic research carried out on the species.
Subspecies
Two subspeciesSubspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
are recognized:
- Atelocynus microtis microtis, Sclater, 1882.
- Atelocynus microtis sclateri, J. A. Allen, 1905