Hi Victor You are right I too feel that the Portughese missionaries have given their surnames to the converts. I hail from Tuticorin which was once a small fishery town and has a couple of dozens of Machados who are not related to each other at all. Do you have any documental reference to our hypothesis? It would be interesting. I belong to a community who are heriditarily taken up fishing as profession? I wonder if all Machados are? Now I am a researcher (marine geologist) residing in Trivandrum. You could be wrong because I could not come across any Machados who are native of Trivandrum.