What is the world's largest barrel sponge?

Screen Shot 2014-05-08 at 10.51.20 AMIt is probably this 2.5 meter (8.2 feet) diameter giant that was a tourist attraction for scuba divers visiting Curaçao in the Caribbean in the early 1990s.  Unfortunately frequent touching by scuba divers likely caused lesions that lead to an infection of the sponge tissue (show as the dark spot pointed to by the arrow in the photo).  By mid-May of 1997 only a large piece of the outer edge sponge remained.  Other barrel sponges in the area were were not impacted suggesting that it was indeed the touching by divers that led to the sponge’s demise.  Through the research of my student Shane Stone and myself, this specimen is so far the largest documented specimen.

Nagelkerken, I. 2000 Barrel sponge bows out. Reef Encounter 28, 14-15.