Deffinatly not Colomesus asellus. I searched all the puffer images I could yesterday trying to ID that puffer, but no luck. I thought someone with the puffer aqualog book might have ID'd it by now.
you know, its hard to say from that one picture at that one particular level. the big stripes make it look like an off-color asellus, but the little dots and the green make me think, um, green-spotted puffer sorry, that was kinda "duh".
hard to see from the pics but if im seeing it right looks very much like the ceylons (fluviatilis) that a lfs round this way had recently - very much like a large figure 8 but without the eyespot at the base of the dorsal fin.