Basically, the Mar Thoma Church is what I'd call "Syrian rite Anglican".
They started in the 1800's when contacts were made between Anglican missionaries and Orthodox leaders. The Anglicans were able to convince two Orthodox teachers (they were priests too, I think) to embrace Reformation theology. Once they "converted" these guys, they set out to "reform" the Orthodox Church, to rid it of all the "excess", and get back to basics. They translated the Orthodox liturgy from Syriac into Malayalam, but omitted a lot of stuff that wouldn't jive with Protestantism. Because it was in Malayalam, the people understood it, and many went along with them, believing that their interpretation was what the Liturgy actually meant, rather than thinking that these guys had the boldness to edit it to suit their reformed theology. They sent one of their clerical members to Antioch seeking his episcopal consecration so that they could have bishops. Despite all warnings from Indian Church leaders who knew what these guys were up to, the Patriarch of Antioch ordained one of them as bishop and sent him to India. He then helped start the new "church". They have a simplified liturgy that basically follows the Syrian rite, but the theology is all Protestant.
There are other things I could say, but it's all on the internet if you look (I could recommend a website or two if you're interested). They'll admit everything they've done, and all their reformation leanings, because they feel it was a good thing. Even from their accounts, you might be shocked. But these guys follow the Syrian rite...there are others in the Anglican communion in India who are just out and out Western Anglicans.
Not very eloquent, I know, but that's the basic story.