I saw this catfish while diving in Grand Cenote, about 100 miles Southwest of Cancun. There were several of them around this root mass. Technically, they were in the cavern zone (within sight of daylight) but I was told they are found in the cave section occasionaly as well. Length is about 8".
Sorry for the poor image quality, these are grabbed from video frames.
Sorry for the poor image quality, these are grabbed from video frames.