| Sechuran fox[1] | |
|---|---|
 | |
Scientific classification | |
| 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 | |
TheSechuran fox (Lycalopex sechurae), also called thePeruvian desert fox or theSechuran zorro, is a smallSouth American species ofcanid closely related to other South American "false" foxes orzorro. It gets its name for being found in theSechura Desert in northwesternPeru.[1]
It is one of ten extant species of canid endemic toSouth America. This fox inhabits a narrow region west of theAndes 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 underLycalopex, the Sechuran fox was classed under theDusicyon genus established by Oldfield Thomas in 1914, and was later moved to thePseudalopex (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 theMiocene 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 theInternational 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; largelyhabitat 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 grayagouti 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-likecanine teeth.[8]
The species has 74chromosomes.[9]
First identified in theSechura Desert, the fox inhabits arid environments in southwesternEcuador and westernPeru, 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 theAndes 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 theLycalopex genus wasDusicyon australis (or theFalkland Islands wolf) which went extinct in 1876.[7]
Several fossils of Sechuran foxes are known from the latePleistocene of Ecuador and Peru, close to the modern range. Genetic analysis suggests that the closest living relative of the Sechuran fox isDarwin's fox, which is native toChile.[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 rapidradiation. 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 theGreat American Biotic Interchange in theMiocene era, via the Panamanianland bridge.[11]
Multiple studies[12][5][13] have supported that South American canids (of which theLycalopex genus makes up over half of these species) aremonophyletic, 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 theLycalopex genus is believed to be theFalkland 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 extantL. sechurae occupies today).[5]
ThePleistocene 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 toDusicyon 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 littlegene flow as compared to the other fiveLycalopex 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 otherLycalopex 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 lowheterozygosity and small population size, which can similarly be seen inLycalopex fulvipes (or Darwin's fox), which also inhabits a very narrow region west of the Andes, except it includes an island population.[5]
Within theLycalopex 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 theLycalopex 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 ofL. 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 isnocturnal, and spends the daylight hours in aden 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 onseed pods, especially those of the shrubProsopis juliflora and ofcaper bushes, as well as the fruit ofCordia andmito 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 asNear Threatened by theIUCN.[10]
