Ask any expert about the importance of thermostats for regulating vivarium temperature and you’ll get a unanimous answer - that they are essential. Unfortunately some pet stores, and even specialist reptile strores, sell “start kits” including small vivariums and heat mats which don’t include a thermostat.

There are many, many documented cases of injury and even death to reptiles from heating equipment so this practise is foolish and dangerous. I found a superb forum post today which gives experimental results and proves without doubt just how dangerous it can be to use heat mats without a stat… In the experiment the mat surface reached over 150F (over 65C) which is seriously hot… certainly hot enough to cause injury to many reptiles.

You can read the post, and see photos of the actual thermometer readings here

While most boas won’t be heated by a mat (I recommend ceramic bulbs for most species, but some terrestrial species such as Rosy boas can be heated by mat) and so the snake won’t ever be lying directly on the heat source a thermostat is still absolutely essential to correctly and safely maintain temperatures.