do mexican salamanders is a type of neotenic salamanders

Yes, Mexican salamanders, specifically the Ambystoma mexicanum or axolotl, are known for their neoteny. Neoteny is a biological process where an organism retains juvenile characteristics into adulthood.

In the case of axolotls:

• They retain their larval or juvenile features like external gills and a cartilaginous (not bony) skeleton throughout their lives.
• They do not undergo the typical metamorphic changes that other salamander species do, which would involve losing gills and developing lungs for terrestrial respiration, and adapting their body form for life on land.
• Axolotls are able to reproduce while still in their aquatic larval stage.

The retention of these juvenile features allows axolotls to live comfortably in water throughout their entire lifespan, making them facultative neoteny species. This condition is advantageous for their aquatic lifestyle but is also what makes them sensitive to environmental changes, as they are not adapted to leave water. Their neotenic state has made axolotls a popular model organism in scientific research, particularly in the fields of regeneration and developmental biology.