Boa sigma | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Reptilia |
Order: | Squamata |
Suborder: | Serpentes |
Family: | Boidae |
Genus: | Boa |
Species: | B. sigma |
Binomial name | |
Boa sigma (Smith, 1943) | |
Distribution range for Boa sigma | |
Synonyms [2] | |
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Boa sigma, known commonly as the Mexican west coast boa constrictor, is a species of snake in the family Boidae. The species is endemic to western Mexico. Boa sigma has previously been regarded as conspecific with Boa constrictor , and later with Boa imperator ; however, in 2016, it was suggested on genetic grounds that Boa sigma should be regarded as a separate species.
Boa sigma was originally described as Constrictor constrictor sigma by Hobart Muir Smith in 1943. [3] [4] The subspecies only included snakes from the Islas Marías, and it did not receive wide recognition; instead, it was synonymized with the mainland subspecies Boa constrictor imperator by many authors. [4] [5] [6]
In the 21st century, genetic studies revealed that Boa constrictor is a species complex. First, Boa constrictor imperator was elevated to species level, but it was soon recognized that there was another species nested within the new species Boa imperator. According to Card et al. (2016), the name Boa sigma is available for this third species. [4] However, further research is needed because the genetic study of Card et al. didn't include samples from the Islas Marías, from where the holotype and the paratypes were collected. [4] [7] [8] Despite this uncertainty, Boa sigma has been widely accepted as a valid species. [2] [9]
Suárez-Atilano et al. (2014) identified two lineages of Boa imperator with a divergence date of about 5.2 Ma. [10] However, Card et al. (2016) found the divergence date of these lineages, which they recognized as Boa imperator and Boa sigma, to be around 14 Ma. [4] Both divergence dates could be explained with the rise of biogeographical barriers. [11]
Boa sigma is distributed along the Pacific Coast of Mexico west of the Isthmus of Tehuantepec. [12] The northernmost records are from Sonora, [13] where the species can reach altitudes of 1,420 metres (4,659 ft). [14] Within the distribution range of Boa sigma, the three islands of the Islas Marías are included: María Madre, María Magdalena and María Cleofas. [12]
Based on species distribution modelling, Boa sigma lives mainly within the tropical dry forest ecoregion, whereas Boa imperator seems to prefer areas with more precipitation. [11] In Oaxaca, there is a contact zone between these two species, but it is unclear whether or not hybridization occurs there. [2] [11]
In eastern and southern Sonora, it is widely believed that Boa sigma, locally known as corúa, corúga, corúva, culebrón or limacoa, is the guardian of water (guardiana del agua). Unlike other snakes, Boa sigma is protected by rural Sonorans, because it is thought that killing the boa would cause the spring (aguaje) to dry up. [15] [16] [17]
Amphisbaenia is a group of usually legless squamates, comprising over 200 extant species. Amphisbaenians are characterized by their long bodies, the reduction or loss of the limbs, and rudimentary eyes. As many species have a pink body and scales arranged in rings, they have a superficial resemblance to earthworms. While the genus Bipes retains forelimbs, all other genera are limbless. Although superficially similar to other limbless vertebrates including the snakes, legless lizards, and blind lizards, recent phylogenetic studies suggest that they are most closely related to wall lizards of the family Lacertidae. Amphisbaenians are widely distributed, occurring in North America, Europe, Africa, South America, Western Asia and the Caribbean. Most species are less than 6 inches (15 cm) long.
Boa is a genus of boas found in Mexico, the Caribbean, and Central and South America. Five extant species, and one extinct, are currently recognized.
Constriction is a method used by several snake species to kill or subdue their prey. Although some species of venomous and mildly venomous snakes do use constriction to subdue their prey, most snakes which use constriction lack venom. The snake strikes at its prey and holds on, pulling the prey into its coils or, in the case of very large prey, pulling itself onto the prey. The snake then wraps one or two loops around the prey, forming a constriction coil. The snake monitors the prey's heartbeat to ascertain it is dead. This can be a physically demanding and potentially dangerous procedure for the snake, because its metabolism is accelerated up to sevenfold and it becomes vulnerable to attack by another predator.
The desert rosy boa is a species of snake in the family Boidae. The desert rosy boa is native to the American Southwest and Baja California and Sonora in Mexico. The desert rosy boa is one of four species in the boa family native to the continental United States, the other three being the coastal rosy boa and the two species of rubber boas (Charina).
Aridoamerica denotes an ecological region spanning Northern Mexico and the Southwestern United States, defined by the presence of the culturally significant staple foodstuff Phaseolus acutifolius, a drought-resistant bean. Its dry, arid climate and geography stand in contrast to the verdant Mesoamerica of present-day central Mexico into Central America to the south and east, and the higher, milder "island" of Oasisamerica to the north. Aridoamerica overlaps with both.
The Gran Desierto de Altar is one of the major sub-ecoregions of the Sonoran Desert, located in the State of Sonora, in northwest Mexico. It includes the only active erg dune region in North America. The desert extends across much of the northern border of the Gulf of California, spanning more than 100 kilometres (62 mi) east to west and over 50 kilometres (31 mi) north to south. It constitutes the largest continuous wilderness area within the Sonoran Desert.
The Cuban boa, also known as the Cuban tree boa and by locals as maja de Santa María, is a very large species of snake in the family Boidae. With lengths exceeding 5 m (16 ft) and a relatively heavy build, the Cuban boa is one of the largest snakes in the world. The species is native to Cuba and some nearby islands. No subspecies are currently recognized.
The Alethinophidia are an infraorder of snakes that includes all snakes other than blind snakes and thread snakes. Snakes have long been grouped into families within Alethinophidia based on their morphology, especially that of their teeth. More modern phylogenetic hypotheses using genetic data support the recognition of 19 extant families, although the taxonomy of alethinophidian snakes has long been debated, and ultimately the decision whether to assign a particular clade to a particular Linnaean rank is arbitrary.
Boa imperator is a large, heavy-bodied, nonvenomous species of snake in the genus Boa that is commonly kept in captivity. Boa imperator is part of the family Boidae and is found in Mexico, Central America and South America west of the Andes Mountains. It is commonly called the Central American boa, northern boa, Colombian boa, common boa and common northern boa.
Boa orophias, the Saint Lucia boa or San Lucia boa, is a species of snake in the family Boidae. The species is endemic to Saint Lucia. Boa orophias was described as a full species by Carl Linnaeus in 1758, but many later authors have classified it as a subspecies of Boa constrictor. According to the IUCN Red List, Boa orophias is a species, which they have listed as Endangered.
The sea urchins of the Gulf of California live between the coasts of the Baja California Peninsula to the west and mainland state of Sonora, Mexico to the east. The northern boundary is the lateral band of land with the remains of the Colorado River Delta, and the southern is the Pacific Ocean.
The boa constrictor, also known as the common boa, is a species of large, non-venomous, heavy-bodied snake that is frequently kept and bred in captivity. The boa constrictor is a member of the family Boidae. The species is native to tropical South America. A staple of private collections and public displays, its color pattern is highly variable yet distinctive. Four subspecies are recognized. This article focuses on the species Boa constrictor as a whole, and on the nominate subspecies B. c. constrictor.
The Crawl Cay boa is a dwarf Boa imperator population that reaches a maximum length of about 5 feet. Characteristics of this snake are the very gray background colour with black speckling which is also on the head. The snakes have saddling like the common boa, which continue onto the tail.
Boa imperator sabogae is a subspecies of large, heavy-bodied snake. It is a member of the family Boidae.
Hypsiglena unaocularus, commonly known as the Islas Revillagigedo night snake or Clarión night snake, is a species of small colubrid snake endemic to Clarion Island, initially described from a single specimen collected by William Beebe in 1936. During the next several decades, scientists were unable to detect any trace of the snake in their field studies. After an intensive search in 2013, a team of scientist identified 11 snakes that matched the original description of the species. They conducted a series of DNA tests to confirm that the Islas Revillagigedo nightsnake, formerly viewed as the subspecies Hypsiglena torquata unaocularis, is genetically distinct from related mainland snakes and should be recognized as a full species. While never formally declared extinct, this species remained absent from scientific literature due to two main factors: its home on Clarion is extremely remote and only accessible by military escort, significantly restricting the number of biologists who can access this area, and the snake's secretive, nocturnal behavior and dark coloration make it difficult to detect in the field. Because of the lack of follow-up sightings, scientists long presumed that Beebe had provided an incorrect locality for his specimen.
Pseudaspididae is a small family of elapoid snakes. They were formerly placed as a subfamily of the Lamprophiidae, but have been more recently identified as a distinct family.
The Sonoran Desert tortoise, or Morafka's desert tortoise, is a species of tortoise native to the Sonoran Desert.