On Jul 4, 2013 I spotted similar a crab in Arippa forest in a small stream but the pictures were of low quality.
http://www.projectnoah.org/spottings/37273159
On Sept 14 2014 I spotted this orange crab near a water canal inside a broken shack outside the forest area 4 km away from the Peppara Dam entrance.
It was found when ploughing in ground. Took it and moved it to a puddle in a sacred grove close by.
Found near a hill stream in the hills surrounding valanjagaram waterfalls.