The Axolotl is a species of salamander that is only found in the lakes in Xochimilco, Central Mexico. They require deep water lake in order to survive in with large amount of aquatic vegetations. This species lives permanently in water and unlike other salamanders, this species does not undergo complete metamorphosis (Luis et al, 2010).
Axolotl can be characterized by their large head, lidless eyes, underdeveloped limbs with long thin digits, long body and three pairs of gill stalks behind the head. Wild Axolotl are a dark brown/tan with olive under belly (Frost et al, 1984). Axolotl also have four pigmentation genes which changes the colour of the Axolotl. These genes are leucistic (pale pink with black eyes), axanthic (grey with black eyes), albino (gold with gold eyes) and melanoid (black) (Dunson & Dunson, 1974).
Melanoid Axolotl
by Ian Bride (below) and Albino Axolotl by Henk Wallays (above).
Female Axolotl’s become heavy with eggs when it is time
to breed while males have an enlarged gland that produces jelly to protect his
sperm. Both male and female Axolotls reach breeding maturity at the age of 1
year and can breed up to 8-10 years. Axolotl eggs take about 2 weeks to hatch
and young Axolotl have an internal yolk sac that can sustain them for a week.
After 2 weeks, the young Axolotl are large enough to feed on crustaceans/shrimp
(Gresens, 2004).
The main threat to the Axolotl is pollution of their
natural environment. Urbanization and tourism have led to an increased in
pollution in the water ways that contains the vegetation that the Axolotl rely
on. Pollution has also affected the lake where the Axolotl currently reside in,
adding to the risk of extinction due the Axolotl been found nowhere in the world
(Luis et al, 2010).
Next time, we will be covering a species of bee that is
under threat.
References
Dunson, M.K. & Dunson, M.K. 1974, "Ultrastructure
of pigment cells in wild type and color mutants of the Mexican axolotl",
Cell and Tissue Research, vol. 151, no. 2, pp. 259-268.
Frost, S.K., Briggs, F. & Malacinski, G.M. 1984,
"A color atlas of pigment genes in the Mexican axolotl ( Ambystoma mexicanum)",
Differentiation, vol. 26, no. 1, pp. 182-188.
Gresens, J. 2004, "An Introduction to the Mexican
Axolotl ( Ambystoma mexicanum )", Lab Animal, vol. 33, no. 9, pp. 41-47.
Luis Zambrano, Paola Mosig Reidl, Jeanne McKay, Richard
Griffiths, Brad Shaffer, Oscar Flores-Villela, Gabriela Parra-Olea, David Wake
2010. Ambystoma mexicanum . The IUCN Red List of Threatened Species 2010:
e.T1095A3229615.
Picture references
https://www.iucnredlist.org/species/1095/3229615
Melanoid Axolotl
https://www.iucnredlist.org/species/1095/3229615
Albino Axolotl
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