Valentini Puffer with bump under skin

[blazemore]

I've got a Valentini Puffer that I've had for about 3 years now and it has recently (past few months) developed some sort of bump underneath the skin near its jaw. Any idea what it is? There don't appear to be any abrasions or external wounds. It's still eating like a pig and is very active. I was unable to get a very good shot, but here's what I've got.

I also made a short video clip which makes it a little easier to see.

http://blaze.spicelab.net/puffer.wmv

Thanks.

 

[blazemore]

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