Hi , as per your query i would like to tell you that as per Tamil Nadu. Dr. M.G.R medical university Guindy, Chennai there are 6 super specialities for MD siddha which include
Maruthuvam

Gunapadam

Sirappu Maruthuvam

Kuzhandai Maruthuvam

Noi Nadal

Nanju Maruthuvam

Hope this helps