Sechuran fox [1] | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Order: | Carnivora |
Family: | Canidae |
Genus: | Lycalopex |
Species: | L. sechurae |
Binomial name | |
Lycalopex sechurae Thomas, 1900 | |
Sechuran fox range | |
Synonyms | |
Pseudalopex sechurae |
The Sechuran fox (Lycalopex sechurae), also called the Peruvian desert fox or the Sechuran zorro, is a small South American species of canid closely related to other South American "false" foxes or zorro. It gets its name for being found in the Sechura Desert in northwestern Peru. [1]
It is one of ten extant species of canid endemic to South America. This fox inhabits a narrow region west of the Andes Mountains running along the coastline of Peru and southern Ecuador. More specifically, in dry areas such as savannah-like deserts, cliff-sides, along the western side of the Andes mountains, and beaches. [3] The Sechuran Fox is known by the common names Sechura desert fox and Peruvian desert fox. The etymology of its scientific name comes from the Greek "lycos" meaning "wolf," and "alopex" meaning "fox". [3] Before it was classified under Lycalopex , the Sechuran fox was classed under the Dusicyon genus established by Oldfield Thomas in 1914, and was later moved to the Pseudalopex (meaning "false fox") genus by A. Langguth in 1975. [4]
The Sechuran fox is one of the many canid species that evolved from the ancestral canid(s) in the Miocene era. Through the rapid radiation of South American canids, [5] the Sechuran fox has evolved some traits that have possibly lent themselves to the species' survival, and which aid in distinguishing them from other members of this genus. [3] While there is not currently a thorough understanding of this species' evolution, some recent studies have produced notable contributions to this endeavor. [6] [7] [5]
A total population estimate is not currently specified by the International Union for the Conservation of Nature (IUCN), but one 2022 study estimates it to be around 5,000. [5] The main threats to this species currently are anthropogenic; largely habitat destruction through deforestation, and hunting (though to a smaller extent). [3]
The Sechuran fox is small for a canid, weighing 2.6 to 4.2 kg (5.7 to 9.3 lb), with a head-and-body length of 50 to 78 cm (20 to 31 in) and a tail of 27 to 34 cm (11 to 13 in). Its fur is gray agouti over most of the body, fading to white or cream coloured on the underparts. There are reddish-brown markings on the backs of the ears, around the eyes, and on the legs. The muzzle is dark grey, and a grey band runs across the chest. Its tail is tipped with black. It has small teeth, adapted to feed on insects and dry plants, with fox-like canine teeth. [8]
The species has 74 chromosomes. [9]
First identified in the Sechura Desert, the fox inhabits arid environments in southwestern Ecuador and western Peru, at elevations from sea level to at least 1,000 metres (3,300 ft), and possibly much higher. Within this region it has been reported from the western foothills of the Andes down to the coast, inhabiting deserts, dry forests, and beaches. [10] There are no recognised subspecies.
While more studies are required to understand the complete lineage of this species, it has been proposed that the most recent ancestor of the Lycalopex genus was Dusicyon australis (or the Falkland Islands wolf) which went extinct in 1876. [7]
Several fossils of Sechuran foxes are known from the late Pleistocene of Ecuador and Peru, close to the modern range. Genetic analysis suggests that the closest living relative of the Sechuran fox is Darwin's fox, which is native to Chile. [10]
The arrival of the first canid ancestor to South America, and the subsequent divergence into the ten extant canid species (including the Sechuran fox), is an example of remarkably rapid radiation. Details of this recent diversification are not well understood, perhaps the biggest unknown being how many invasive ancestor canid species migrated into South America. However, it is accepted that this occurred during the Great American Biotic Interchange in the Miocene era, via the Panamanian land bridge. [11]
Multiple studies [12] [5] [13] have supported that South American canids (of which the Lycalopex genus makes up over half of these species) are monophyletic, sharing one common ancestor 3.5 million to 4 million years ago. [5] [13] The Sechuran fox was the second out of the six Lycalopex species to diverge from its sister taxon [6] approximately 1.3 million years after the first canid species arrived. The ancestor to the Lycalopex genus is believed to be the Falkland Islands wolf (Dusicyon australis) [12] around 1.4-0.81 million years ago. [5] [12] It is theorized that the main ancestral lineage that migrated from North America split into two, one migrating out east of the Andes, and one going west of the Andes. [5] It is suggested that an ancestral Lycalopex lineage, possibly migrated to the west-Andean region about 1 million years ago, likely during the rise of arid, savannah-like habitats (the sort of habitats that the extant L. sechurae occupies today). [5]
The Pleistocene era was a significant time in the history of this rapid species divergence. It has been suggested in multiple studies that during this period, and into the early Holocene era, there was considerable contraction and expansion of glaciers that resulted in significant shifts in climate of and around the Andes mountains, [12] which was and is still a key driver of speciation. [14] This climate change is believed to have altered habitable areas of some species. [5]
The Sechuran fox's relation to Dusicyon australis has been suggested by a study from Perini et al. (2009). [12] While they were not the first to suspect D. australis as the sister taxa, through their analyses they claim to support this relationship with 87% Bayesian Posterior Probability. [12] The Sechuran fox also appears to have experienced very little gene flow as compared to the other five Lycalopex species. [5] Being only the second species of its genus to diverge from the common ancestor/sister taxa, the Sechuran fox has a high degree of genetic isolation from the other Lycalopex species, as well as a relatively distinct mitochondrial DNA phylogeny. [6]
Additionally, the Sechuran fox's genome exhibits a substantially low degree of autosomal heterozygosity, or genetic variability, especially in contrast with many other South American canids both within and outside of its genus. [5] There is a proposed correlation between low heterozygosity and small population size, which can similarly be seen in Lycalopex fulvipes (or Darwin's fox), which also inhabits a very narrow region west of the Andes, except it includes an island population. [5]
Within the Lycalopex genus, the Sechuran fox is not strikingly distinct from the other species, though morphological differences are still present. It is the smallest out of all the Lycalopex species and lacks red fur on its body, contrasting with other species in this genus. [6] Certain dental features may be important to note when examining possible adaptations, for example, molar sizes seen in fossils of L. sechurae are longer than the molars seen in more recent specimens. [3]
The versatility of this species has possibly lent itself to its survival. For example, when ecological conditions allow, it is omnivorous, but is capable of surviving on a completely vegetarian diet. [3] It has been suggested that vegetarianism may have influenced the aforementioned decrease in molar size. [3]
It is also thought that the Sechuran fox may have an ability to survive without water for lengthy periods, as suggested by the sparse water availability in its usual habitats. [3] Among mammals, this is not a common ability. A specific duration they can survive without water has not been featured in the literature as of yet, as this requires more studies to confirm.[ citation needed ]
The Sechuran fox is nocturnal, and spends the daylight hours in a den dug into the ground. It is generally solitary, although occasionally seen travelling in pairs. Pups are born in October and November, although little else is known of its reproductive behavior. [15]
The fox is an opportunistic feeder, and its diet varies widely depending on the season and local habitat. It has been found to feed on seed pods, especially those of the shrub Prosopis juliflora and of caper bushes, as well as the fruit of Cordia and mito plants, and is capable of surviving on an entirely herbivorous diet when necessary. More commonly, however, it also eats insects, rodents, bird eggs, and carrion as a part of its diet. [16] It can probably survive for long periods of time without drinking, subsisting on the water in its food. [8] Sechuran fox can disperse as many plant species as other more specialized dispensers, such as phyllostomid bat and white-tailed deer. [17]
Sechuran foxes are common in Ecuador. They have been known to prey on local livestock, such as chickens, and are hunted both to reduce such attacks and so that their body parts can be used in local handicrafts, folk medicine, or magical rituals. [10]
The animal is considered at Low Risk in Ecuador, and hunting is not permitted in Peru without a licence. The species is listed as Near Threatened by the IUCN. [10]
Canidae is a biological family of dog-like carnivorans, colloquially referred to as dogs, and constitutes a clade. A member of this family is also called a canid. The family includes three subfamilies: the Caninae, and the extinct Borophaginae and Hesperocyoninae. The Caninae are known as canines, and include domestic dogs, wolves, coyotes, foxes, jackals and other species.
The Falkland Islands wolf, also known as the warrah and occasionally as the Falkland Islands dog, Falkland Islands fox, warrah fox, or Antarctic wolf, was the only native land mammal of the Falkland Islands. This endemic canid became extinct in 1876, the first known canid to have become extinct in historical times.
The culpeo, also known as Culpeo zorro, Andean zorro, Andean fox, Paramo wolf, Andean wolf, and colpeo fox, is a species of South American fox. Despite the name, it is not a true fox, but more closely related to wolves and jackals. Its appearance resembles that of foxes due to convergent evolution.
Dusicyon is an extinct genus of South American canids.
The bat-eared fox is a species of fox found on the African savanna. It is the only extant species of the genus Otocyon and considered a basal canid species. Fossil records indicate this canid first appeared during the middle Pleistocene.
The South American foxes (Lycalopex), commonly called raposa in Portuguese, or zorro in Spanish, are a genus from South America of the subfamily Caninae. Despite their name, they are not true foxes, but are a unique canid genus more closely related to wolves and jackals than to true foxes; some of them resemble foxes due to convergent evolution. The South American gray fox, Lycalopex griseus, is the most common species, and is known for its large ears and a highly marketable, russet-fringed pelt.
The gray fox, or grey fox, is an omnivorous mammal of the family Canidae, widespread throughout North America and Central America. This species and its only congener, the diminutive island fox of the California Channel Islands, are the only living members of the genus Urocyon, which is considered to be genetically sister to all other living canids. Its species name cinereoargenteus means "ashen silver".
Caniformia is a suborder within the order Carnivora consisting of "dog-like" carnivorans. They include dogs, bears, raccoons, and mustelids. The Pinnipedia are also assigned to this group. The center of diversification for the Caniformia is North America and northern Eurasia. Caniformia stands in contrast to the other suborder of Carnivora, the Feliformia, the center of diversification of which was in Africa and southern Asia.
The crab-eating fox, also known as the forest fox, wood fox, bushdog or maikong, is an extant species of medium-sized canid endemic to the central part of South America since at least the Pleistocene epoch. Like South American foxes, which are in the genus Lycalopex, it is not closely related to true foxes. Cerdocyon comes from the Greek words kerdo and kyon (dog) referring to the dog- and fox-like characteristics of this animal.
Darwin's fox or Darwin's zorro is an endangered canid from the genus Lycalopex. It is also known as the zorro chilote or zorro de Darwin in Spanish and lives in Nahuelbuta National Park, the Cordillera de Oncol, Cordillera Pelada in mainland Chile and Chiloé Island. This small, dark canine weighs 1.8 to 3.95 kg, has a head-and-body length of 48 to 59 cm and a tail that is 17.5 to 25.5 cm. Darwin's fox displays no key differences between male and female other than the fact that the male has a broader muzzle. Males display no territorial behavior and are not aggressive towards other males roaming around their territory.
The short-eared dog, also known as the short-eared zorro or small-eared dog, is a unique and elusive canid species endemic to the Amazonian basin. This is the only species assigned to the genus Atelocynus.
The hoary fox or hoary zorro, also known as raposinha-do-campo in Brazil, is a species of zorro or "false" fox endemic to Brazil. Unlike many other foxes, it feeds primarily on small invertebrates such as insects.
The South American gray fox, also known as the Patagonian fox, the chilla or zorro gris, is a South American species of Lycalopex in the Canidae family, which includes dogs, wolves, jackals, coyotes and foxes, among other canids. It is endemic to the southern parts of Argentina and Chile, primarily Patagonia and Tierra Del Fuego.
El Angolo is a game reserve in northern Peru. It is considered part of the Noroeste Biosphere Reserve, which includes Cerros de Amotape National Park and Tumbes National Reserve, as declared by UNESCO in 1977.
Caninae is the only living subfamily within Canidae, alongside the extinct Borophaginae and Hesperocyoninae. They first appeared in North America, during the Oligocene around 35 million years ago, subsequently spreading to Asia and elsewhere in the Old World at the end of the Miocene, some 7 million to 8 million years ago.
Dusicyon avus is an extinct species of cerdocyonine canid in the genus Dusicyon, native to South America during the Pleistocene and Holocene epochs. It was medium to large, about the size of a German shepherd. It was closely related to the Falkland Islands wolf or warrah (Dusicyon australis), which descended from a population of D. avus. It appears to have survived until very recently, perhaps 400 years ago.
Dusicyon cultridens or Dusicyon patagonicus cultridens is an extinct canid species in the genus Dusicyon. However, the classification of this species is poorly researched and debatable. Some scientists place this species in the genera Canis and Lycalopex.
The domestic dog was introduced to South America between 5,500 and 2,500 BCE from North America. They occupied the Andes region and spread into the Amazonian Basin relatively recently, in the 20th century. Today, very few of the original South American dogs remain, mostly replaced with introduced breeds from Eurasia.
Cerdocyonina is an extant subtribe of the canines and is exclusively endemic to the Americas. Often described to be "fox-like" in appearance and behavior, they are more closely related to the wolf-like canids such as Canis than they are to the fox genus Vulpes. Its members are colloquially known as the South American canids and there are 10 extant species. They are sometimes referred to as South American foxes in the older literature, but the term zorro has been recommended by mammalogists to avoid confusion with the true foxes of the tribe Vulpini, which includes the genus Vulpes.