Snakes are an animal found on a few planets.
Barsoom
Reptiles are not common upon Barsoom, and it was widely believed for that snakes were extinct. John carter however encountered some of these creatures in the caverns between the valley dor and the underground omean sea, revealing that some still live. They are similar to earth snake, but their venom would make the cobra de capello seem as harmless as an angleworm
Va-nah
Although not much is known about the interior world of the moon there is a toxic reptile that is somewhat like a snake called a Rympth.
Earth
The mangani of africa call snakes Histah
Amtor
On amtor there are many types of snakes, when Carson Napier was locked in the room of seven doors the room was flooded with many types of snakes. Snakes with horns, sabe-like fangs, and with ears. Many colors also appeared in teh room, blue, red, green, white, and purple were noted. Aswell a huge twenty foot specimen was noted, this snake was able to with assistance from the smaller snakes kill a Tharban