WadeF wrote:
I'm guessing it's sand.
Yes it is. White sand from Indian Ocean coast.
And since last week, he has changed his outfit again; now he's in a
Turritella terebra shell.
B T W, I have just recognized that after molted, this Indo has got weird features: see the last segment of his right second walking leg - it looks swollen; while the small pincer has a small chitinous "horn"; I thought it was a sand grain, but in fact, it is an integral part of his legs !