Bolitoglossa
Encyclopedia
Bolitoglossa also called Tropical climbing salamanders or Web-footed Salamanders is a genus of salamander
s in the Plethodontidae family. Their range is Central and South America: Mexico
, Colombia
, Venezuela
, Ecuador
, Peru
, northeastern Brazil
, and central Bolivia
. These arboreal and terrestrial
, Neotropical salamanders of the Bolitoglossa genus make up the largest genus in the order Caudata consisting of approximately one-fourth of all known species of salamanders. Adult salamanders range anywhere from 45mm to 200mm in length depending on their specific species. They are notorious for their webbed feet, as indicated from their name, and have significantly more webbing than any other species outside their genus with the exception of the Cave-dwelling Mexican Bolitoglossine Chiropterotriton magnipes. Although webbed feet are a common characteristic of these salamanders, only about half of the species in this genus contain webbed feet.
). It is particularly helpful to the salamander in escaping attacks from its predators. Once the tail has been lost, it can regenerate one time. After this regeneration, the tail is incapable of separation with regeneration.
Natural selection is thought to have resulted in genetic changes from physical adaptation. The main differences that have developed from natural selection affect the skull and bones of the feet in these salamanders. Due to these primary changes, secondary changes are believed to have followed, including:
Phylogeny of this genus is partially dependent on its variations in bone structure due to the effects of natural selection over a long period of time.
Classification of this genus is primarily accomplished through analysis of the salamanders’ DNA. This has proven to be the most effective and accurate way of classifying this genus.
Salamander
Salamander is a common name of approximately 500 species of amphibians. They are typically characterized by a superficially lizard-like appearance, with their slender bodies, short noses, and long tails. All known fossils and extinct species fall under the order Caudata, while sometimes the extant...
s in the Plethodontidae family. Their range is Central and South America: 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...
, 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...
, 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...
, 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...
, 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....
, northeastern 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...
, and central 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...
. These arboreal and terrestrial
Terrestrial animal
Terrestrial animals are animals that live predominantly or entirely on land , as compared with aquatic animals, which live predominantly or entirely in the water , or amphibians, which rely on a combination of aquatic and terrestrial habitats...
, Neotropical salamanders of the Bolitoglossa genus make up the largest genus in the order Caudata consisting of approximately one-fourth of all known species of salamanders. Adult salamanders range anywhere from 45mm to 200mm in length depending on their specific species. They are notorious for their webbed feet, as indicated from their name, and have significantly more webbing than any other species outside their genus with the exception of the Cave-dwelling Mexican Bolitoglossine Chiropterotriton magnipes. Although webbed feet are a common characteristic of these salamanders, only about half of the species in this genus contain webbed feet.
Hand and foot morphology
Hand and foot morphology is strikingly diverse in an otherwise morphologically uniform group. While just under half of these species contain webbing between their fingers and toes, the remaining species experience little to no webbing and undergo elongation of their fingers and toes throughout development. Ultimately, the variation of foot morphology within this genus is primarily due to natural selection. Derived characteristics correspond to arboreal vs. terrestrial salamanders.- Webbed fingers – natural selection to improve terrestrial movement through water.
- Elongated fingers – natural selection of increased suction efficiency, favoring a larger surface area of the foot. This also selects for a decreased body size, enabling the salamander to cling trees more easily.
Tail autotomy
Tail autotomy refers to the salamanders’ ability to release or loose their tail if necessary. This is a common characteristic of nearly all salamanders and lizards. (See autotomyAutotomy
Autotomy or self amputation is the act whereby an animal severs one or more of its own appendages, usually as a self-defense mechanism designed to elude a predator's grasp...
). It is particularly helpful to the salamander in escaping attacks from its predators. Once the tail has been lost, it can regenerate one time. After this regeneration, the tail is incapable of separation with regeneration.
Poison
B. rostrata and B. subpalmata are two rare examples of poisonous salamanders within their genus. The poison is secreted through their skin as an antipredator mechanism. It is particularly toxic to certain snake species, rendering them immobile and unresponsive to external stimuli upon initial contact. The common defense tactic of these two species is to remain still in the presence of the snake until it makes initial contact (usually by the flickering of its tongue), and then run away as the paralytic poison begins to take effect in the snake.Natural selection
Tropical adaptation of the Bolitoglossa genus is thought to have evolved from N. American Plethodontids. Natural selection is responsible for morphological changes shifting from those supporting temperate environments to those supporting tropical environments such as Panama and Costa Rica.Natural selection is thought to have resulted in genetic changes from physical adaptation. The main differences that have developed from natural selection affect the skull and bones of the feet in these salamanders. Due to these primary changes, secondary changes are believed to have followed, including:
- Body size
- Additional ossificationOssificationOssification is the process of laying down new bone material by cells called osteoblasts. It is synonymous with bone tissue formation...
of bones - Webbing
- Ear structure
Phylogeny of this genus is partially dependent on its variations in bone structure due to the effects of natural selection over a long period of time.
Hybridization
The first documented case of hybridization in tropical salamanders occurred between B. frankini and B. resplendens. This hybridization has taken a pervasive effect on the morphology of B. resplendens, whereas B. frankini seemed to maintain its same physical structure. According to scientists, this is the only known salamander hybrid in the world today.Taxonomy
Derived characteristics of the genus Bolitoglossa has led to their classification based on this specific list of characters:- Tongue and hypobranchial apparatusApparatusApparatus may refer to:*Technical term for body of the Soviet and post-Soviet governments *Machine*Equipment*Critical apparatus, the critical and primary source material that accompanies an edition of a text-See also:*Fire apparatus...
- Epibranchial Number
- embryos having a single epibranchial
- Tail Autotomy
- Brain stem motor control
- Bone structure of Jaws, CranialCranialCranial may refer to:* an adjective related to the cranium* Anatomical terms of location* Cranial cavity* Cranial Osteopathy...
, and inner ear - ChromosomeChromosomeA chromosome is an organized structure of DNA and protein found in cells. It is a single piece of coiled DNA containing many genes, regulatory elements and other nucleotide sequences. Chromosomes also contain DNA-bound proteins, which serve to package the DNA and control its functions.Chromosomes...
number- diploid number of chromosomes is 26
- Development
Classification of this genus is primarily accomplished through analysis of the salamanders’ DNA. This has proven to be the most effective and accurate way of classifying this genus.
Species
117 species are currently assigned to this genus.EWLINE
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