The axolotl is an urodele amphibian, unique to certain lakes in central Mexico. Axolotl stems from Nahuatl axolotl: atl water and xolotl monster; aquatic monster. The axolotl, Ambystoma mexicanum, is also known as a Mexican “walking fish”.
The axolotl is from the family of salamanders (Protesu mexianus L., Siredonhumboldti B.). Physically, the axolotl looks like a giant tadpole. Adults measure from 15 cm to 45 cm, most commonly about 20 centimeters ( inches) in length. The head of the axolotl is wide and the eyes have no lids. The limbs are underdeveloped and axolotls have long, thin digits. There are four digits in the thoracic extremities and five digits in the abdominal extremities. Along the back is a comb-like feature stretching to the tail.
Primarily, the axolotl feeds by suctioning, during which the gill slits are closed. Axolotls feed on mollusks, worms, insect larva, crustaceans and a few types of fish. They can grow to live 15 years.
Origin
Axolotls originated in central Mexico less than ten thousand years ago (Wanderer 2018). Historically, they are endemic to lake systems in central, southern regions of Mexico, that have increasingly been drained and/or reduced.
Pigmentation
Axolotls in the wild are naturally a variation of dark brown/grey/black with gold speckles and/or whitish markings with olive overtone. Axolotls can be mistaken for rocks, as the natural dark color serves as camouflage,. As they age, they appear almost black.
Neoteny
The axolotl is rare among amphibians, with the extraordinary privilege of exhibiting neoteny. It is a larva and reaches adulthood without undergoing metamorphosis. The axolotl stays permanently in a state of reproducing its entire life. Neoteny seems to be a survival mechanism, in aquatic environments of high altitudes, such as mountains and hills, with little food sources. In this way, axolotls can reproduce and survive in the form of a larval stage, a stage that is aquatic and requires less amount of food. Adult axolotls remain aquatic and gilled.
Special features
Axolotls have distinct features, external gills and a caudal fin. A feature of the axolotl is that it is capable of regeneration of entire lost appendages. Another feature is the large embryo, which allows viewing of the development of vertebrae. The genetics of the variants of pigmentation are also special features. The axolotl lives permanently in water, and in very rare cases will an adult axolotl leave aquatic life.
Ecology and Conservation
Due to the reduction of the lake system of Xochimilco, the population of wild axolotls is declining. Wild axolotls are critically endangered and under heavy pressure. Axolotls are on the Red List of threatened species. It is estimated that there are less than 1,500 axolotls in the wild. Conservation efforts in Mexico have provided protected areas and refuge, primarily in the lake system of Xochimilco. Other regions of Mexico, including Tlaxcala have recently provided protected areas.
The National Autonomous University of Mexico initiated the Chinampa-Refugio Project.
Author: AllMexico.store
References
Axolotl Sanctuary Ajolotario Miquiztli Xolotl Pachuca Pimvs – Home | Facebook
Global Press Journal Saving the Axolotl, Mexico’s ‘Walking Fish,’ Requires Creative Efforts (globalpressjournal.com)
National Geographic