Pannagas and Uragas - snake-like demonic beings, related to Nagas. Most likely, they were variety of the last.
See my photos of serpent-like creatures in the section "Disappeared inhabitants of the Earth in the sculpture and painting of Thailand and Cambodia"
The section "Aboriginal inhabitants"
Read my works "Great antediluvian civilizations of Fomorians, Rakshasas, Viyevichs and Nagas. General characteristic and their role in the world history" and "Giants and titans - predecessors and contemporaries of people. What was the growth of gods and demons?"