My crocea has em too. I dont know what they are. I saw one of em at night. I tried to remove one with my finger and felt I was popping a bubble (i got very scared casue i thought maybe it was a nudi >_<" ). I saw another one on there last night. Unfortunately I have no idea what they are and havent been able to see them clearly for that matter. They look like a little bubble to me.. (on my clam anywho)